Zoom 5370 User manual

After the cable modem connects to your cable service provider, open your Web
browser on the computer that’s connected to your cable modem. Then refresh the
screen or try to go to a Web site. Many service providers, including Comcast,
typically bring your browser to a registration page. In that case, follow the
instructions on this registration page to register your modem. (Comcast Users
Only: If the activation page does not appear please go to
If this is a first-time cable modem installation (that is, you are NOT
replacing an “old” cable modem), do this:
1Connect a “live” coaxial cable from your cable service provider to your cable
modem First check that the wire in the center of the cable’s connector is
centered, straight, and clean. If the coaxial cable has a screw-on
connector, turn the connector clockwise when tightening the cable onto the
Zoom cable modem. (If you’re not sure a cable is live, you can see whether
you get a good TV signal when that cable is used with a working TV set-top
box.) Here are some ways you can get the live cable:
MODEL 5370 CABLE MODEM
QUICK START
This Quick Start describes how to connect your Zoom Model 5370 cable modem to
a cable modem service. This lets your cable modem provide Internet access to a
computer or other device connected to the cable modem’s Ethernet LAN Jack. If
that device is a wireless router, wireless devices can connect through the router and
Zoom cable modem to the Internet.
Package Contents
•Cable modem
•Power cube
•Ethernet RJ-45 cable
•This Quick Start flyer
Before installing your cable modem, please read this.
You need to connect the cable modem to a cable modem service that uses any of
the popular DOCSIS standards – 3.0, 2.0, or 1.1. If you need to get cable modem
service, please speak with your cable service provider.
Your cable service provider will need to know your modem's MAC ADDRESS and
may need the account number of your cable service. Your MAC Address is printed
on a label on the side of your modem and is called CM MAC. Your account
number can be found on your bill, or you can call your service provider to get your
account number. You need to provide this information when you order cable modem
service, or when calling the cable company after installing your modem, or by filling
out the account setup web page that may appear when you first connect your cable
modem to your provider’s network. You may also be asked for your cable modem's
model name and number, which is ZOOM 5370. If you need the modem's serial
number, you can find it near the MAC address on the label.
If you are replacing an “old” cable modem, do this:
1Disconnect the coaxial cable from the old cable modem and connect it to
your Zoom modem. If the coaxial cable has a screw-on connector, turn the
connector clockwise when tightening the cable onto the Zoom cable
modem.
2If there’s an Ethernet cable plugged into the old cable modem, unplug the
Ethernet cable from the old cable modem and plug it into the Zoom cable
modem’s LAN jack.
3Connect the Zoom power cube between the Zoom cable modem and a live
power jack. DO NOT use your old cable modem’s power cube on your
Zoom cable modem. If your cable modem’s Power Button is not already
pressed in, press the button in to turn on your cable modem.
4Go to “Now that your cable modem is connected, do this.” below.
Coaxial Cable Cable TV Jack
¾You have a cable TV cable (“coaxial cable”) with a male connector on the
end that isn’t connected to anything. This cable may be coming out of a
wall or connected to a cable TV jack.
¾There’s a cable TV jack in your wall. You can connect a cable TV “coaxial
cable” between that jack and your cable modem. You may have a
coaxial cable, possibly one that came with a cable modem starter kit from
your cable service provider. If you don’t have a coaxial cable, you can
get one at most electronics stores. You want one with a screw-in male F
connector at each end, with a length that works for your installation.
¾If you don’t have an available cable TV cable or wall jack, use a coaxial “T
adapter” or “splitter” available from most electronics
retailers (see example at right). Make sure you get one
designed for cable modems and/or cable TV. These
typically have one female IN jack and two female OU
jacks. You can disconnect a live cable from your TV
set-top box and screw it into the IN jack of the splitter.
Then connect one coaxial cable from an OUT jack to
your TV set-top box and another coaxial cable from the other OUT jac
your cable modem. You can see that this approach uses one splitter and
2 additional coaxial cables, each of which has male connectors on each
end. Some electronics retailers carry the Zoom Cable Modem Connectio
Kit which has an excellent splitter and 2 coaxial cables packaged togethe
at a reasonable price. You can also purchase splitters and coaxial ca
separately if you prefer to do that, perhaps because you need a special
length of coaxial cable.
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ble
2Connect the supplied Ethernet cable between the cable modem’s yellow
LAN jack and a computer’s Ethernet jack. We recommend that you do this
even if you later plan to connect the cable modem to a router.
3Connect the Zoom power cube between the Zoom cable modem and a live
power jack. If your cable modem’s Power Button is not already pressed in,
press the button in to turn on your cable modem.
4Go to “Now that your cable modem is connected, do this.” below.
Now that your cable modem is connected, do this.
It normally takes 5 to 30 minutes to establish an Internet link the first time a cable
modem connects to a cable service provider. This allows the cable modem to
connect to the appropriate channels for communication. You’ll see the DS, US, and
Online modem lights on your cable modem flashing until the Online light stays
steady green to signal success.
www.xfinity.com/internetsetup to activate your modem.)
If no registration page appears after following the browser instructions above, you
need to call your cable company to register your modem. Below is a list of some
major cable service providers’ phone numbers to call if you need to activate your
cable modem. Note that this list is subject to change.
Comcast 1 [phone] Time Warner 1 [phone]
Cox 1 [phone] Cable One 1 [phone]
RCN 1 [phone]
Once your cable modem is registered either online or through a conversation with
someone at your cable service provider, your service provider will provision your
cable modem service. Typically this takes less than 5 minutes, but in some cases
this may take up to 30 minutes to complete.
To check that your cable modem is working, open your browser and go to a familiar
Web site. If it works, Congratulations! Installation is complete for a single PC. If
you want to connect your cable modem to a router, please continue directly below.
If your cable modem is NOT working, see Troubleshooting Tips on the back of this
Quick Start for help.
How to connect your cable modem to a router instead of a
computer. This connection is optional, done after the cable
modem is working with a computer.
1The router should not be plugged in or powered up. If it is, unplug it.
2Unplug the cable modem’s Ethernet cable from your computer and plug it into
the Router’s WAN port.
3Power-up the router. Make sure the router’s Power button is ON. Wait for the
router to complete its power-up sequence.
4The LAN light of the modem should be lit to show the Ethernet connection to
your router. Follow your router’s instructions for setting up the router and
connected devices.
5Using a computer connected to the router, open the computer’s browser and go
to a website to check that the connection between your cable modem and router
is working properly. If it works, Congratulations! Installation is complete.
If the cable modem worked when connected to a computer but does not work
when connected to a router, try the following:
¾First try shutting down and restarting the router; if that doesn’t help,
then try shutting down and restarting each computer connected to the
router.
¾Power off your cable modem, router and any computers connected to
the router. Power on the cable modem and allow it time to
resynchronize with the cable system. Once the cable modem is
synchronized with its online light steady green, power up your router,
then power up any computers connected to your router.
¾You may also need to check that the DHCP client on the router’s WAN
port is enabled. If you need help, look in your router’s manual or
contact your router manufacturer.
¾If that does not solve the problem, you may need to contact your cable
service provider and give them the MAC address of the router’s WAN
port.

After the cable modem connects to your cable service provider, open your Web
browser on the computer that’s connected to your cable modem. Then refresh the
screen or try to go to a Web site. Many service providers, including Comcast,
typically bring your browser to a registration page. In that case, follow the
instructions on this registration page to register your modem. (Comcast Users
Only: If the activation page does not appear please go to
If this is a first-time cable modem installation (that is, you are NOT
replacing an “old” cable modem), do this:
1Connect a “live” coaxial cable from your cable service provider to your cable
modem First check that the wire in the center of the cable’s connector is
centered, straight, and clean. If the coaxial cable has a screw-on
connector, turn the connector clockwise when tightening the cable onto the
Zoom cable modem. (If you’re not sure a cable is live, you can see whether
you get a good TV signal when that cable is used with a working TV set-top
box.) Here are some ways you can get the live cable:
MODEL 5370 CABLE MODEM
QUICK START
This Quick Start describes how to connect your Zoom Model 5370 cable modem to
a cable modem service. This lets your cable modem provide Internet access to a
computer or other device connected to the cable modem’s Ethernet LAN Jack. If
that device is a wireless router, wireless devices can connect through the router and
Zoom cable modem to the Internet.
Package Contents
•Cable modem
•Power cube
•Ethernet RJ-45 cable
•This Quick Start flyer
Before installing your cable modem, please read this.
You need to connect the cable modem to a cable modem service that uses any of
the popular DOCSIS standards – 3.0, 2.0, or 1.1. If you need to get cable modem
service, please speak with your cable service provider.
Your cable service provider will need to know your modem's MAC ADDRESS and
may need the account number of your cable service. Your MAC Address is printed
on a label on the side of your modem and is called CM MAC. Your account
number can be found on your bill, or you can call your service provider to get your
account number. You need to provide this information when you order cable modem
service, or when calling the cable company after installing your modem, or by filling
out the account setup web page that may appear when you first connect your cable
modem to your provider’s network. You may also be asked for your cable modem's
model name and number, which is ZOOM 5370. If you need the modem's serial
number, you can find it near the MAC address on the label.
If you are replacing an “old” cable modem, do this:
1Disconnect the coaxial cable from the old cable modem and connect it to
your Zoom modem. If the coaxial cable has a screw-on connector, turn the
connector clockwise when tightening the cable onto the Zoom cable
modem.
2If there’s an Ethernet cable plugged into the old cable modem, unplug the
Ethernet cable from the old cable modem and plug it into the Zoom cable
modem’s LAN jack.
3Connect the Zoom power cube between the Zoom cable modem and a live
power jack. DO NOT use your old cable modem’s power cube on your
Zoom cable modem. If your cable modem’s Power Button is not already
pressed in, press the button in to turn on your cable modem.
4Go to “Now that your cable modem is connected, do this.” below.
Coaxial Cable Cable TV Jack
¾You have a cable TV cable (“coaxial cable”) with a male connector on the
end that isn’t connected to anything. This cable may be coming out of a
wall or connected to a cable TV jack.
¾There’s a cable TV jack in your wall. You can connect a cable TV “coaxial
cable” between that jack and your cable modem. You may have a
coaxial cable, possibly one that came with a cable modem starter kit from
your cable service provider. If you don’t have a coaxial cable, you can
get one at most electronics stores. You want one with a screw-in male F
connector at each end, with a length that works for your installation.
¾If you don’t have an available cable TV cable or wall jack, use a coaxial “T
adapter” or “splitter” available from most electronics
retailers (see example at right). Make sure you get one
designed for cable modems and/or cable TV. These
typically have one female IN jack and two female OU
jacks. You can disconnect a live cable from your TV
set-top box and screw it into the IN jack of the splitter.
Then connect one coaxial cable from an OUT jack to
your TV set-top box and another coaxial cable from the other OUT jac
your cable modem. You can see that this approach uses one splitter and
2 additional coaxial cables, each of which has male connectors on each
end. Some electronics retailers carry the Zoom Cable Modem Connectio
Kit which has an excellent splitter and 2 coaxial cables packaged togethe
at a reasonable price. You can also purchase splitters and coaxial ca
separately if you prefer to do that, perhaps because you need a special
length of coaxial cable.
T
k to
n
r
ble
2Connect the supplied Ethernet cable between the cable modem’s yellow
LAN jack and a computer’s Ethernet jack. We recommend that you do this
even if you later plan to connect the cable modem to a router.
3Connect the Zoom power cube between the Zoom cable modem and a live
power jack. If your cable modem’s Power Button is not already pressed in,
press the button in to turn on your cable modem.
4Go to “Now that your cable modem is connected, do this.” below.
Now that your cable modem is connected, do this.
It normally takes 5 to 30 minutes to establish an Internet link the first time a cable
modem connects to a cable service provider. This allows the cable modem to
connect to the appropriate channels for communication. You’ll see the DS, US, and
Online modem lights on your cable modem flashing until the Online light stays
steady green to signal success.
www.xfinity.com/internetsetup to activate your modem.)
If no registration page appears after following the browser instructions above, you
need to call your cable company to register your modem. Below is a list of some
major cable service providers’ phone numbers to call if you need to activate your
cable modem. Note that this list is subject to change.
Comcast 1 [phone] Time Warner 1 [phone]
Cox 1 [phone] Cable One 1 [phone]
RCN 1 [phone]
Once your cable modem is registered either online or through a conversation with
someone at your cable service provider, your service provider will provision your
cable modem service. Typically this takes less than 5 minutes, but in some cases
this may take up to 30 minutes to complete.
To check that your cable modem is working, open your browser and go to a familiar
Web site. If it works, Congratulations! Installation is complete for a single PC. If
you want to connect your cable modem to a router, please continue directly below.
If your cable modem is NOT working, see Troubleshooting Tips on the back of this
Quick Start for help.
How to connect your cable modem to a router instead of a
computer. This connection is optional, done after the cable
modem is working with a computer.
1The router should not be plugged in or powered up. If it is, unplug it.
2Unplug the cable modem’s Ethernet cable from your computer and plug it into
the Router’s WAN port.
3Power-up the router. Make sure the router’s Power button is ON. Wait for the
router to complete its power-up sequence.
4The LAN light of the modem should be lit to show the Ethernet connection to
your router. Follow your router’s instructions for setting up the router and
connected devices.
5Using a computer connected to the router, open the computer’s browser and go
to a website to check that the connection between your cable modem and router
is working properly. If it works, Congratulations! Installation is complete.
If the cable modem worked when connected to a computer but does not work
when connected to a router, try the following:
¾First try shutting down and restarting the router; if that doesn’t help,
then try shutting down and restarting each computer connected to the
router.
¾Power off your cable modem, router and any computers connected to
the router. Power on the cable modem and allow it time to
resynchronize with the cable system. Once the cable modem is
synchronized with its online light steady green, power up your router,
then power up any computers connected to your router.
¾You may also need to check that the DHCP client on the router’s WAN
port is enabled. If you need help, look in your router’s manual or
contact your router manufacturer.
¾If that does not solve the problem, you may need to contact your cable
service provider and give them the MAC address of the router’s WAN
port.

After the cable modem connects to your cable service provider, open your Web
browser on the computer that’s connected to your cable modem. Then refresh the
screen or try to go to a Web site. Many service providers, including Comcast,
typically bring your browser to a registration page. In that case, follow the
instructions on this registration page to register your modem. (Comcast Users
Only: If the activation page does not appear please go to
If this is a first-time cable modem installation (that is, you are NOT
replacing an “old” cable modem), do this:
1Connect a “live” coaxial cable from your cable service provider to your cable
modem First check that the wire in the center of the cable’s connector is
centered, straight, and clean. If the coaxial cable has a screw-on
connector, turn the connector clockwise when tightening the cable onto the
Zoom cable modem. (If you’re not sure a cable is live, you can see whether
you get a good TV signal when that cable is used with a working TV set-top
box.) Here are some ways you can get the live cable:
MODEL 5370 CABLE MODEM
QUICK START
This Quick Start describes how to connect your Zoom Model 5370 cable modem to
a cable modem service. This lets your cable modem provide Internet access to a
computer or other device connected to the cable modem’s Ethernet LAN Jack. If
that device is a wireless router, wireless devices can connect through the router and
Zoom cable modem to the Internet.
Package Contents
•Cable modem
•Power cube
•Ethernet RJ-45 cable
•This Quick Start flyer
Before installing your cable modem, please read this.
You need to connect the cable modem to a cable modem service that uses any of
the popular DOCSIS standards – 3.0, 2.0, or 1.1. If you need to get cable modem
service, please speak with your cable service provider.
Your cable service provider will need to know your modem's MAC ADDRESS and
may need the account number of your cable service. Your MAC Address is printed
on a label on the side of your modem and is called CM MAC. Your account
number can be found on your bill, or you can call your service provider to get your
account number. You need to provide this information when you order cable modem
service, or when calling the cable company after installing your modem, or by filling
out the account setup web page that may appear when you first connect your cable
modem to your provider’s network. You may also be asked for your cable modem's
model name and number, which is ZOOM 5370. If you need the modem's serial
number, you can find it near the MAC address on the label.
If you are replacing an “old” cable modem, do this:
1Disconnect the coaxial cable from the old cable modem and connect it to
your Zoom modem. If the coaxial cable has a screw-on connector, turn the
connector clockwise when tightening the cable onto the Zoom cable
modem.
2If there’s an Ethernet cable plugged into the old cable modem, unplug the
Ethernet cable from the old cable modem and plug it into the Zoom cable
modem’s LAN jack.
3Connect the Zoom power cube between the Zoom cable modem and a live
power jack. DO NOT use your old cable modem’s power cube on your
Zoom cable modem. If your cable modem’s Power Button is not already
pressed in, press the button in to turn on your cable modem.
4Go to “Now that your cable modem is connected, do this.” below.
Coaxial Cable Cable TV Jack
¾You have a cable TV cable (“coaxial cable”) with a male connector on the
end that isn’t connected to anything. This cable may be coming out of a
wall or connected to a cable TV jack.
¾There’s a cable TV jack in your wall. You can connect a cable TV “coaxial
cable” between that jack and your cable modem. You may have a
coaxial cable, possibly one that came with a cable modem starter kit from
your cable service provider. If you don’t have a coaxial cable, you can
get one at most electronics stores. You want one with a screw-in male F
connector at each end, with a length that works for your installation.
¾If you don’t have an available cable TV cable or wall jack, use a coaxial “T
adapter” or “splitter” available from most electronics
retailers (see example at right). Make sure you get one
designed for cable modems and/or cable TV. These
typically have one female IN jack and two female OU
jacks. You can disconnect a live cable from your TV
set-top box and screw it into the IN jack of the splitter.
Then connect one coaxial cable from an OUT jack to
your TV set-top box and another coaxial cable from the other OUT jac
your cable modem. You can see that this approach uses one splitter and
2 additional coaxial cables, each of which has male connectors on each
end. Some electronics retailers carry the Zoom Cable Modem Connectio
Kit which has an excellent splitter and 2 coaxial cables packaged togethe
at a reasonable price. You can also purchase splitters and coaxial ca
separately if you prefer to do that, perhaps because you need a special
length of coaxial cable.
T
k to
n
r
ble
2Connect the supplied Ethernet cable between the cable modem’s yellow
LAN jack and a computer’s Ethernet jack. We recommend that you do this
even if you later plan to connect the cable modem to a router.
3Connect the Zoom power cube between the Zoom cable modem and a live
power jack. If your cable modem’s Power Button is not already pressed in,
press the button in to turn on your cable modem.
4Go to “Now that your cable modem is connected, do this.” below.
Now that your cable modem is connected, do this.
It normally takes 5 to 30 minutes to establish an Internet link the first time a cable
modem connects to a cable service provider. This allows the cable modem to
connect to the appropriate channels for communication. You’ll see the DS, US, and
Online modem lights on your cable modem flashing until the Online light stays
steady green to signal success.
www.xfinity.com/internetsetup to activate your modem.)
If no registration page appears after following the browser instructions above, you
need to call your cable company to register your modem. Below is a list of some
major cable service providers’ phone numbers to call if you need to activate your
cable modem. Note that this list is subject to change.
Comcast 1 [phone] Time Warner 1 [phone]
Cox 1 [phone] Cable One 1 [phone]
RCN 1 [phone]
Once your cable modem is registered either online or through a conversation with
someone at your cable service provider, your service provider will provision your
cable modem service. Typically this takes less than 5 minutes, but in some cases
this may take up to 30 minutes to complete.
To check that your cable modem is working, open your browser and go to a familiar
Web site. If it works, Congratulations! Installation is complete for a single PC. If
you want to connect your cable modem to a router, please continue directly below.
If your cable modem is NOT working, see Troubleshooting Tips on the back of this
Quick Start for help.
How to connect your cable modem to a router instead of a
computer. This connection is optional, done after the cable
modem is working with a computer.
1The router should not be plugged in or powered up. If it is, unplug it.
2Unplug the cable modem’s Ethernet cable from your computer and plug it into
the Router’s WAN port.
3Power-up the router. Make sure the router’s Power button is ON. Wait for the
router to complete its power-up sequence.
4The LAN light of the modem should be lit to show the Ethernet connection to
your router. Follow your router’s instructions for setting up the router and
connected devices.
5Using a computer connected to the router, open the computer’s browser and go
to a website to check that the connection between your cable modem and router
is working properly. If it works, Congratulations! Installation is complete.
If the cable modem worked when connected to a computer but does not work
when connected to a router, try the following:
¾First try shutting down and restarting the router; if that doesn’t help,
then try shutting down and restarting each computer connected to the
router.
¾Power off your cable modem, router and any computers connected to
the router. Power on the cable modem and allow it time to
resynchronize with the cable system. Once the cable modem is
synchronized with its online light steady green, power up your router,
then power up any computers connected to your router.
¾You may also need to check that the DHCP client on the router’s WAN
port is enabled. If you need help, look in your router’s manual or
contact your router manufacturer.
¾If that does not solve the problem, you may need to contact your cable
service provider and give them the MAC address of the router’s WAN
port.

Cable Modem Rear Panel Troubleshooting Tips
LAN
Connect your Ethernet cable between this port and a
computer or router.
RESET
Press this button for 5 seconds in the unlikely event
that you need to restore factory default settings.
RF
Connect your coaxial cable line to this port.
POWER
Connect the supplied power cube to this port.
ON/OFF
Push the button in to turn the power ON. Push the
button again to turn the power OFF.
Please note the following:
¾Do not block the modem vents in any way.
¾Do not place the modem near a heating or air conditioning duct, in direct
sunlight, anywhere susceptible to drastic temperature changes, or where it’s
very hot or very cold.
Front Panel LEDs
Your cable modem has several lights on its front panel to help you monitor the cable
modem’s status.
LIGHT COLOR DESCRIPTION
Power Green ON: Power is supplied to the cable modem
OFF: Power is not supplied to the cable modem
DS
Downstream
sync
Green or
Blue
Green Blinking: Scanning for DS channel
Green ON: Synchronized on 1 channel only
Blue Blinking: Negotiating bonded channel(s)†
Blue ON: Bonded with 1 or more channels
OFF: Downstream channel is inactive
US
Upstream sync Green or Blue
Green Blinking: Ranging is in progress
Green ON: Ranging is complete; operate on
1 channel
Blue Blinking: Negotiating bonded channel(s)†
Blue ON: Bonded with 1 or more channels
OFF: Upstream channel is inactive
Online Green
Blinking: Cable interface is acquiring IP, Time, and
configuration
ON: Cable modem is online
OFF: Cable modem is offline
LAN
Ethernet LAN
port
Green Blinking: Data is flowing and the Ethernet link is
connected
Green: Connected
OFF: No Ethernet link detected
†If Blue light blinks continuously, this indicates partial service (at least one designated
channel has not completed bonding). You should still get high Internet speeds, but your
cable modem service provider may want to know so they can adjust their network.
Problem: I cannot access the Internet. What should I do first?
Solution: Make sure that your Cable Modem’s MAC address is registered with your
cable provider. When your provider’s representative or setup software asks
for your MAC address, you can find the CM MAC address on your modem’s
side label. If you are having a problem, you may need to check with your
cable service provider to make sure the service provider set up its system
properly for your cable modem.
¾Make sure your Cable Modem’s Power button is ON and that the cable
modem’s power cube is plugged into a live power outlet.
¾Check your Cable Modem’s Ethernet and coaxial cable connections. Make
sure the coaxial cable is tightly connected. Make sure that the Ethernet
cable that connects a computer or router to your Cable Modem is plugged
in all the way on both ends.
¾Power off your modem for at least 10 seconds, then power it back on.
¾Restart your computer or other devices connected to the Cable Modem.
This ensures that they receive a correct IP address.
Problem: I cannot access the Internet. My Power light is on, my Downstream
and Upstream lights are on or blinking, and my Online light is on.
Solution: If you are using your computer’s Ethernet port, check that there is a good
connection between your computer and the modem/router’s Ethernet port.
Check that the light for that port is on or flashing.
Problem: I cannot access the Internet. My Power light is on, and my
Downstream and Upstream lights are on or blinking. My Online light
won’t stay on.
Solution: Try the following:
¾Check to see that your cable TV is working. If it isn’t, contact your cable
service provider. There may be a bad connection to the cable to your
home or location.
¾Check with your cable service provider to make sure that your cable data
service is available and running.
¾In some cases, the cable signal may be weak or noisy. If possible, see if
the cable modem/router works better when it’s connected as near as
possible to where the coaxial cable comes into your home.
¾If you have a splitter between the cable modem/router and the wall,
remove the splitter and connect the cable modem/router directly to the
wall. A splitter is a small device that has a single coax cable on one side
and 2 coax cables on the other side. If this fixes the problem, you may
need to get a better splitter.
¾If the problem persists, you may need to ask your cable service provider to
check the signal quality on your cable connection.
Problem: What do I do if my cable service provider wants me to access the
Configuration Manager?
Solution: Make sure you have a connection between your computer or other device
and the cable modem.
1On your computer, open a browser and type in the address
192.168.100.1 Enter
User Name: admin
Password: admin
2Now you will see status information about your cable modem and its
connection that you can read back to your service provider.
Problem: What if I'm told that my Model 5370 cable modem isn't approved for my
cable modem service?
Solution: This modem has been certified by CableLabs and by Comcast, Time Warner
Cable, and other cable modem service providers. You can often find a list of
certified modems on the Web site of your cable service provider. Beware of
installers who try to get you to use their cable modem instead of a Zoom
cable modem. Some of these installers provide bad information because they
are misinformed or because they earn a fee for providing their cable modem.
If the installer tells you that a cable modem provided by him or the service
provider is "free", that's almost never true. When in doubt, check the cable
service provider’s Web site!
•In the unlikely event that you are told that your Zoom modem is not approved by
your cable modem service, please email us at [e-mail] or call us at
[phone].
•Approval information for CableLabs, Comcast, and other service providers is
available at www.zoomtel.com/cableOK
If You Need Help
We encourage you to register your product and to notice the many support options
available from Zoom. Please go to www.zoomtel.com/techsupport From here you can
register your modem and/or contact our technical support experts and/or use our
intelligent database SmartFactstm and/or get warranty information.
US: [phone]
Return of Defective Units
Please contact your local distributor or retailer for factory-authorized repair or replacement of
your in-warranty defective product. If you are unable to reach your distributor or retailer, you
can contact Zoom Technical Support in the United States by calling: [phone]
Please note that you are responsible for any charges (including brokerage or customs and
duties) associated with shipping the defective unit to Zoom for repair. During the first year
Zoom will pay return ground shipping to the customer in the continental U.S. After the first
year you may be required to pay a shipping and handling fee. Any applicable customs, duties
and brokerage charges to import the product are your responsibility.
Limited Warranty
Zoom Telephonics, Inc. warrants this product against defects in material and workmanship for
a warranty period of 2 years. To read the full warranty, please see
www.zoomtel.com/cablewarranty
Safety Issues & Warnings
WARNING: Risk of electric shock. Do NOT expose to water or moisture.
¾The cable modem is a high-performance communications device designed for home and
office environments.
¾Do NOT use the cable modem outdoors. Keep the cable modem in an environment that
is between 0°C and 40°C (between 32°F and 104°F).
¾To avoid overheating the cable modem, do NOT place any object on top of the cable
modem.
¾Do NOT place the cable modem in a confined space.
¾Do NOT restrict the flow of air around the cable modem.
¾The manufacturer assumes no liabilities for damage caused by any improper use of the
cable modem.
¾Make sure the voltages and frequency of the power outlet matches the electrical rating
labels on the power cube.
FCC Statement
This device complies with Class B Part 15 of the FCC Rules. Operation is subject to the following
two conditions: (1) this device may not cause harmful interference, and (2) this device must accept
any interference received, including interference that may cause undesired operation. Only Coaxial
cables are to be used with this device in order to ensure compliance with FCC emissions limits.
Accessories connected to this device by the user must comply with FCC Class B limits. The
manufacturer is not responsible for any interference which results from use of improper cables, or
which results from unauthorized changes or modifications to the device.
Disclaimer
Zoom Telephonics, Inc. (hereinafter “Zoom”) assumes no liabilities with respect to the contents of
this document. Zoom also reserves the right to revise this document or update occasionally the
content hereof without any obligation to notify any person of such revisions or amendments.
Specifications subject to change without notice.
2155-A 27718-EL ©2015

Cable Modem Rear Panel Troubleshooting Tips
LAN
Connect your Ethernet cable between this port and a
computer or router.
RESET
Press this button for 5 seconds in the unlikely event
that you need to restore factory default settings.
RF
Connect your coaxial cable line to this port.
POWER
Connect the supplied power cube to this port.
ON/OFF
Push the button in to turn the power ON. Push the
button again to turn the power OFF.
Please note the following:
¾Do not block the modem vents in any way.
¾Do not place the modem near a heating or air conditioning duct, in direct
sunlight, anywhere susceptible to drastic temperature changes, or where it’s
very hot or very cold.
Front Panel LEDs
Your cable modem has several lights on its front panel to help you monitor the cable
modem’s status.
LIGHT COLOR DESCRIPTION
Power Green ON: Power is supplied to the cable modem
OFF: Power is not supplied to the cable modem
DS
Downstream
sync
Green or
Blue
Green Blinking: Scanning for DS channel
Green ON: Synchronized on 1 channel only
Blue Blinking: Negotiating bonded channel(s)†
Blue ON: Bonded with 1 or more channels
OFF: Downstream channel is inactive
US
Upstream sync Green or Blue
Green Blinking: Ranging is in progress
Green ON: Ranging is complete; operate on
1 channel
Blue Blinking: Negotiating bonded channel(s)†
Blue ON: Bonded with 1 or more channels
OFF: Upstream channel is inactive
Online Green
Blinking: Cable interface is acquiring IP, Time, and
configuration
ON: Cable modem is online
OFF: Cable modem is offline
LAN
Ethernet LAN
port
Green Blinking: Data is flowing and the Ethernet link is
connected
Green: Connected
OFF: No Ethernet link detected
†If Blue light blinks continuously, this indicates partial service (at least one designated
channel has not completed bonding). You should still get high Internet speeds, but your
cable modem service provider may want to know so they can adjust their network.
Problem: I cannot access the Internet. What should I do first?
Solution: Make sure that your Cable Modem’s MAC address is registered with your
cable provider. When your provider’s representative or setup software asks
for your MAC address, you can find the CM MAC address on your modem’s
side label. If you are having a problem, you may need to check with your
cable service provider to make sure the service provider set up its system
properly for your cable modem.
¾Make sure your Cable Modem’s Power button is ON and that the cable
modem’s power cube is plugged into a live power outlet.
¾Check your Cable Modem’s Ethernet and coaxial cable connections. Make
sure the coaxial cable is tightly connected. Make sure that the Ethernet
cable that connects a computer or router to your Cable Modem is plugged
in all the way on both ends.
¾Power off your modem for at least 10 seconds, then power it back on.
¾Restart your computer or other devices connected to the Cable Modem.
This ensures that they receive a correct IP address.
Problem: I cannot access the Internet. My Power light is on, my Downstream
and Upstream lights are on or blinking, and my Online light is on.
Solution: If you are using your computer’s Ethernet port, check that there is a good
connection between your computer and the modem/router’s Ethernet port.
Check that the light for that port is on or flashing.
Problem: I cannot access the Internet. My Power light is on, and my
Downstream and Upstream lights are on or blinking. My Online light
won’t stay on.
Solution: Try the following:
¾Check to see that your cable TV is working. If it isn’t, contact your cable
service provider. There may be a bad connection to the cable to your
home or location.
¾Check with your cable service provider to make sure that your cable data
service is available and running.
¾In some cases, the cable signal may be weak or noisy. If possible, see if
the cable modem/router works better when it’s connected as near as
possible to where the coaxial cable comes into your home.
¾If you have a splitter between the cable modem/router and the wall,
remove the splitter and connect the cable modem/router directly to the
wall. A splitter is a small device that has a single coax cable on one side
and 2 coax cables on the other side. If this fixes the problem, you may
need to get a better splitter.
¾If the problem persists, you may need to ask your cable service provider to
check the signal quality on your cable connection.
Problem: What do I do if my cable service provider wants me to access the
Configuration Manager?
Solution: Make sure you have a connection between your computer or other device
and the cable modem.
1On your computer, open a browser and type in the address
192.168.100.1 Enter
User Name: admin
Password: admin
2Now you will see status information about your cable modem and its
connection that you can read back to your service provider.
Problem: What if I'm told that my Model 5370 cable modem isn't approved for my
cable modem service?
Solution: This modem has been certified by CableLabs and by Comcast, Time Warner
Cable, and other cable modem service providers. You can often find a list of
certified modems on the Web site of your cable service provider. Beware of
installers who try to get you to use their cable modem instead of a Zoom
cable modem. Some of these installers provide bad information because they
are misinformed or because they earn a fee for providing their cable modem.
If the installer tells you that a cable modem provided by him or the service
provider is "free", that's almost never true. When in doubt, check the cable
service provider’s Web site!
•In the unlikely event that you are told that your Zoom modem is not approved by
your cable modem service, please email us at [e-mail] or call us at
[phone].
•Approval information for CableLabs, Comcast, and other service providers is
available at www.zoomtel.com/cableOK
If You Need Help
We encourage you to register your product and to notice the many support options
available from Zoom. Please go to www.zoomtel.com/techsupport From here you can
register your modem and/or contact our technical support experts and/or use our
intelligent database SmartFactstm and/or get warranty information.
US: [phone]
Return of Defective Units
Please contact your local distributor or retailer for factory-authorized repair or replacement of
your in-warranty defective product. If you are unable to reach your distributor or retailer, you
can contact Zoom Technical Support in the United States by calling: [phone]
Please note that you are responsible for any charges (including brokerage or customs and
duties) associated with shipping the defective unit to Zoom for repair. During the first year
Zoom will pay return ground shipping to the customer in the continental U.S. After the first
year you may be required to pay a shipping and handling fee. Any applicable customs, duties
and brokerage charges to import the product are your responsibility.
Limited Warranty
Zoom Telephonics, Inc. warrants this product against defects in material and workmanship for
a warranty period of 2 years. To read the full warranty, please see
www.zoomtel.com/cablewarranty
Safety Issues & Warnings
WARNING: Risk of electric shock. Do NOT expose to water or moisture.
¾The cable modem is a high-performance communications device designed for home and
office environments.
¾Do NOT use the cable modem outdoors. Keep the cable modem in an environment that
is between 0°C and 40°C (between 32°F and 104°F).
¾To avoid overheating the cable modem, do NOT place any object on top of the cable
modem.
¾Do NOT place the cable modem in a confined space.
¾Do NOT restrict the flow of air around the cable modem.
¾The manufacturer assumes no liabilities for damage caused by any improper use of the
cable modem.
¾Make sure the voltages and frequency of the power outlet matches the electrical rating
labels on the power cube.
FCC Statement
This device complies with Class B Part 15 of the FCC Rules. Operation is subject to the following
two conditions: (1) this device may not cause harmful interference, and (2) this device must accept
any interference received, including interference that may cause undesired operation. Only Coaxial
cables are to be used with this device in order to ensure compliance with FCC emissions limits.
Accessories connected to this device by the user must comply with FCC Class B limits. The
manufacturer is not responsible for any interference which results from use of improper cables, or
which results from unauthorized changes or modifications to the device.
Disclaimer
Zoom Telephonics, Inc. (hereinafter “Zoom”) assumes no liabilities with respect to the contents of
this document. Zoom also reserves the right to revise this document or update occasionally the
content hereof without any obligation to notify any person of such revisions or amendments.
Specifications subject to change without notice.
2155-A 27718-EL ©2015

Cable Modem Rear Panel Troubleshooting Tips
LAN
Connect your Ethernet cable between this port and a
computer or router.
RESET
Press this button for 5 seconds in the unlikely event
that you need to restore factory default settings.
RF
Connect your coaxial cable line to this port.
POWER
Connect the supplied power cube to this port.
ON/OFF
Push the button in to turn the power ON. Push the
button again to turn the power OFF.
Please note the following:
¾Do not block the modem vents in any way.
¾Do not place the modem near a heating or air conditioning duct, in direct
sunlight, anywhere susceptible to drastic temperature changes, or where it’s
very hot or very cold.
Front Panel LEDs
Your cable modem has several lights on its front panel to help you monitor the cable
modem’s status.
LIGHT COLOR DESCRIPTION
Power Green ON: Power is supplied to the cable modem
OFF: Power is not supplied to the cable modem
DS
Downstream
sync
Green or
Blue
Green Blinking: Scanning for DS channel
Green ON: Synchronized on 1 channel only
Blue Blinking: Negotiating bonded channel(s)†
Blue ON: Bonded with 1 or more channels
OFF: Downstream channel is inactive
US
Upstream sync Green or Blue
Green Blinking: Ranging is in progress
Green ON: Ranging is complete; operate on
1 channel
Blue Blinking: Negotiating bonded channel(s)†
Blue ON: Bonded with 1 or more channels
OFF: Upstream channel is inactive
Online Green
Blinking: Cable interface is acquiring IP, Time, and
configuration
ON: Cable modem is online
OFF: Cable modem is offline
LAN
Ethernet LAN
port
Green Blinking: Data is flowing and the Ethernet link is
connected
Green: Connected
OFF: No Ethernet link detected
†If Blue light blinks continuously, this indicates partial service (at least one designated
channel has not completed bonding). You should still get high Internet speeds, but your
cable modem service provider may want to know so they can adjust their network.
Problem: I cannot access the Internet. What should I do first?
Solution: Make sure that your Cable Modem’s MAC address is registered with your
cable provider. When your provider’s representative or setup software asks
for your MAC address, you can find the CM MAC address on your modem’s
side label. If you are having a problem, you may need to check with your
cable service provider to make sure the service provider set up its system
properly for your cable modem.
¾Make sure your Cable Modem’s Power button is ON and that the cable
modem’s power cube is plugged into a live power outlet.
¾Check your Cable Modem’s Ethernet and coaxial cable connections. Make
sure the coaxial cable is tightly connected. Make sure that the Ethernet
cable that connects a computer or router to your Cable Modem is plugged
in all the way on both ends.
¾Power off your modem for at least 10 seconds, then power it back on.
¾Restart your computer or other devices connected to the Cable Modem.
This ensures that they receive a correct IP address.
Problem: I cannot access the Internet. My Power light is on, my Downstream
and Upstream lights are on or blinking, and my Online light is on.
Solution: If you are using your computer’s Ethernet port, check that there is a good
connection between your computer and the modem/router’s Ethernet port.
Check that the light for that port is on or flashing.
Problem: I cannot access the Internet. My Power light is on, and my
Downstream and Upstream lights are on or blinking. My Online light
won’t stay on.
Solution: Try the following:
¾Check to see that your cable TV is working. If it isn’t, contact your cable
service provider. There may be a bad connection to the cable to your
home or location.
¾Check with your cable service provider to make sure that your cable data
service is available and running.
¾In some cases, the cable signal may be weak or noisy. If possible, see if
the cable modem/router works better when it’s connected as near as
possible to where the coaxial cable comes into your home.
¾If you have a splitter between the cable modem/router and the wall,
remove the splitter and connect the cable modem/router directly to the
wall. A splitter is a small device that has a single coax cable on one side
and 2 coax cables on the other side. If this fixes the problem, you may
need to get a better splitter.
¾If the problem persists, you may need to ask your cable service provider to
check the signal quality on your cable connection.
Problem: What do I do if my cable service provider wants me to access the
Configuration Manager?
Solution: Make sure you have a connection between your computer or other device
and the cable modem.
1On your computer, open a browser and type in the address
192.168.100.1 Enter
User Name: admin
Password: admin
2Now you will see status information about your cable modem and its
connection that you can read back to your service provider.
Problem: What if I'm told that my Model 5370 cable modem isn't approved for my
cable modem service?
Solution: This modem has been certified by CableLabs and by Comcast, Time Warner
Cable, and other cable modem service providers. You can often find a list of
certified modems on the Web site of your cable service provider. Beware of
installers who try to get you to use their cable modem instead of a Zoom
cable modem. Some of these installers provide bad information because they
are misinformed or because they earn a fee for providing their cable modem.
If the installer tells you that a cable modem provided by him or the service
provider is "free", that's almost never true. When in doubt, check the cable
service provider’s Web site!
•In the unlikely event that you are told that your Zoom modem is not approved by
your cable modem service, please email us at [email protected] or call us at
[phone].
•Approval information for CableLabs, Comcast, and other service providers is
available at www.zoomtel.com/cableOK
If You Need Help
We encourage you to register your product and to notice the many support options
available from Zoom. Please go to www.zoomtel.com/techsupport From here you can
register your modem and/or contact our technical support experts and/or use our
intelligent database SmartFactstm and/or get warranty information.
US: [phone]
Return of Defective Units
Please contact your local distributor or retailer for factory-authorized repair or replacement of
your in-warranty defective product. If you are unable to reach your distributor or retailer, you
can contact Zoom Technical Support in the United States by calling: [phone]
Please note that you are responsible for any charges (including brokerage or customs and
duties) associated with shipping the defective unit to Zoom for repair. During the first year
Zoom will pay return ground shipping to the customer in the continental U.S. After the first
year you may be required to pay a shipping and handling fee. Any applicable customs, duties
and brokerage charges to import the product are your responsibility.
Limited Warranty
Zoom Telephonics, Inc. warrants this product against defects in material and workmanship for
a warranty period of 2 years. To read the full warranty, please see
www.zoomtel.com/cablewarranty
Safety Issues & Warnings
WARNING: Risk of electric shock. Do NOT expose to water or moisture.
¾The cable modem is a high-performance communications device designed for home and
office environments.
¾Do NOT use the cable modem outdoors. Keep the cable modem in an environment that
is between 0°C and 40°C (between 32°F and 104°F).
¾To avoid overheating the cable modem, do NOT place any object on top of the cable
modem.
¾Do NOT place the cable modem in a confined space.
¾Do NOT restrict the flow of air around the cable modem.
¾The manufacturer assumes no liabilities for damage caused by any improper use of the
cable modem.
¾Make sure the voltages and frequency of the power outlet matches the electrical rating
labels on the power cube.
FCC Statement
This device complies with Class B Part 15 of the FCC Rules. Operation is subject to the following
two conditions: (1) this device may not cause harmful interference, and (2) this device must accept
any interference received, including interference that may cause undesired operation. Only Coaxial
cables are to be used with this device in order to ensure compliance with FCC emissions limits.
Accessories connected to this device by the user must comply with FCC Class B limits. The
manufacturer is not responsible for any interference which results from use of improper cables, or
which results from unauthorized changes or modifications to the device.
Disclaimer
Zoom Telephonics, Inc. (hereinafter “Zoom”) assumes no liabilities with respect to the contents of
this document. Zoom also reserves the right to revise this document or update occasionally the
content hereof without any obligation to notify any person of such revisions or amendments.
Specifications subject to change without notice.
2155-A 27718-EL ©2015