Bully Dog 42215 User manual

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WORKS WITH:
GT Diesel Part# 40420
[phone] | www.bullydog.com
Part # 42215
Document #42215-99 v1.0
2018+ CUMMINS GT BYPASS CABLE
INSTALLATION MANUAL

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2018+ Cummins GT Bypass Cable
CONTENTS
Setup Preview.........................................................................2
Support & pre-tune checklist................................................2
Parts List..................................................................................3
Part 1 ....................................................................................4-6
Pre-Install Checklist.................................................................................... 4
Part 2 .........................................................................................
Updating the GT .........................................................................................4
Part 3
Physical Installation.................................................................................... 5
Part 4
GT Install Process.......................................................................................6

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SETUP PREVIEW
This will guide you through installing the bypass cable kit on your
2018+ Cummins. This kit will be installed before tuning the vehicle
and should stay installed as long as the Bullydog GT is in use. The
black Bypass OBDII block that comes with this kit (with red tag/tape
on it) will be used in place of the black OBDII block that comes with
the Bullydog GT.
PRE-TUNE CHECKLIST
INTERNET ACCESS
In the event that technical support is needed, internet access may be
required to troubleshoot.
ALLOW ENOUGH TIME
Make sure you have at least two hours to complete the unlock and
installation process.
CHECK YOUR BATTERY
Before installation, ALWAYS ensure that the batteries are fully charged. If you
are not sure, connect a battery charger before you begin installation.
TURN ELECTRONICS OFF
Leaving electronics on (including the stereo) may prevent a successful
download. Make sure electronics are o for the entire process.

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2018+ Cummins GT Bypass Cable
BYPASS KIT PARTS CHECKLIST
The following is a list of the items that should be included in the
Cummins Bypass Kit packaging. If you are missing any of the items
please contact technical support at bullydog.com/support.
OBDII Cable Block
USB Bypass Cable

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GT DIESEL PARTS LIST
In addition to the Bypass Kit you will need conrm that you have the GT
parts shown below before proceeding.
GT Diesel
Micro SD Card
Micro SD Card Reader
Mini USB Cable

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2018+ Cummins GT Bypass Cable
UPDATING THE GT DIESEL
Installing the Bully Dog Update Agent software– Windows®
ALL SOFTWARE INCLUDING THE UPDATE AGENT IS NOT MAC
COMPATIBLE. A WINDOWS-BASED PC WILL BE REQUIRED.
1. Go to: bullydog.com and click on the “Support” tab at the top of the page.
2. Locate and click the "Software" option and then click on "Light Duty
Update Agent, Device Updater, and Livelink Downloads". You will see
"Bully Dog Update Agent (Updater for GT devices)". Click to begin
downloading and installing on your computer.
3. Wait for the program to download, then double click and “Run” the
BullyDogDeviceUpdater.exe le if it does not open automatically.
4. Follow the on-screen instructions to complete the installation of the
software.
Connecting the micro SD card
1. The SD card was located in a paper envelope, located in an envelope
inside your GTs original product packaging.
2. Insert the memory card into
the included card reader.
3. Insert the card reader with
memory card to a USB port
on the computer.
If the computer does not read the SD card, try a dierent USB
port. If that does not work, retry this step with the SD card
plugged into the GT Diesel that is referred to in the next step.

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Installing the memory card in the GT Diesel.
1. Remove the card reader from the
computer.
2. Remove the memory card from
the card reader and insert the
memory card into the GT.
Connecting the GT Diesel to computer
1. Connect the GT Diesel to the
computer with the included USB
cable.
2. Press the second button from the
top on the left side of the GT.
3. The GT may display “Initializing
Communication” on the Main Screen.
This is normal and will not change
while the GT is connected to the
computer; there is no need to wait
for the message to disappear to
complete the update process.

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2018+ Cummins GT Bypass Cable
GT PHYSICAL INSTALLATION
WARNING:
Be sure to use the Bypass Cable included with the kit and NOT
the Bully Dog OBDII Harness that came with your GT. Using the
incorrect Cable could cause damage to your vehicles’ ECM.
1. Connect the Bypass Cable
a. Working from the footwell of the driver seat, locate the green terminal
block as pictured. This is typically under the dash towards the rewall
and can be accessed without removing any dash panels. (see the video at :
https://youtu.be/x9rh_x5jbWQ)
2. Plug the white rectangular connector at the end of the Bypass Cable into
an open slot in the green terminal block
a. Plug the mini-USB end of the bypass cable into the Bypass OBDII Block
(with red tag).
3. Install the OBDII Block

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a. Find your vehicles’ diagnostic port (OBDII) under the dash
b. Connect the Bypass OBDII Block (with red tag) to the OBDII port.
4. Install the HDMI cable
a. Connect one end of the HDMI cable to the Bypass OBDII Block (red tag).
b. Run the cable under the dash or weather stripping.
c. Connect the other end of the HDMI cable to the back of the GT.
OBDll Port Location
All OBDll ports are located under the
dash on the drivers side of the vehicle.

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2018+ Cummins GT Bypass Cable
GT INSTALL PROCESS
1. From the GT Main Menu choose “Change Vehicle” and then select your
vehicle from the list that follows.
2. Choose “Install Download” in the main menu.
3. Follow the instructions on your GT screen
4. You will need to turn your key to dierent positions and then choose
“continue”.
5. When tuning is complete, refer to the GT Quick Install Guide for a com-
plete physical installation of the Key On Power Source.”

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2018+ Cummins GT Bypass Cable
[phone] | www.bullydog.com