Anthony Liftgates AC-1600 User manual

Made in the USA
AC
AC-1600
AC-2000
AC-2500
Quality, Reliability, Customer Service
MAINTENANCE MANUAL

Contents
1. General Information .........................4
1.1 Introduction ...........................4
1.2 General Safety.........................4
1.3 State and Federal Regulations ............4
1.3.1 Lighting .........................4
1.3.2 Rear Impact Guards ...............4
1.4 If Maintenance Help is Required ...........4
1.4.1 Maintenance (Dealer) ..............4
1.4.2 Customer Service and Parts (End User)4
1.5 Registration ...........................5
1.6 Warranty .............................5
2. Safety....................................5
2.1 Safety is Your Responsibility ..............5
2.2.1 Personal Protection/Important Information
6
2.2.2 Prohibited Actions . . . . . . . . . . . . . . . . . 6
2.2.3 Hazard Avoidance .................6
2.2 Safety Icons Nomenclature ...............6
2.3 Safety Rules...........................6
2.3.1 Personal Protection................6
2.3.2 Equipment / Tools / Parts ...........7
2.3.3 Battery / Fuel Tank Safety ...........7
2.3.4 Cutting Torch / Welding Safety .......7
2.4 Welding or Grinding Galvanized or Stainless Steel
Material ..................................8
2.4.1 Galvanized Metal..................8
2.4.2 Stainless Steel....................8
3. Nomenclature..............................8
4. Maintenance .............................10
4.1 Monthly Inspection.....................10
4.2 Semi-Annual Inspection.................10
4.3 Check Power Module Fluid Level .........10
4.4 Power Cable Fuse - 200 Amp ............11
4.5 Checking the Power Cable ..............11
4.6 Checking Motor Start Solenoid and Power Cut-off
Solenoid .................................11
4.7 Checking Valve Cartridge and Solenoid ....12
4.8 Solenoid Valve Screen..................12
4.9 Replacing the Solenoid Valve ............12
4.10 Checking Cylinder Piston Seals...........13
4.10.1 Power Down Models ..............13
4.10.2 Gravity Down Models .............13
4.11 Checking System Pressure ..............13
4.12 Checking Flow Control Valve .............14
4.13 Control Switch Fuse - 10 Amp ...........14
5. Troubleshooting Chart ......................15
6. Decals ..................................19

1. General Information
1.1 Introduction
Congratulations on selecting an Anthony Liftgates AC
Conventional liftgate.
859
1.2 General Safety
WARNING Read, Understand, and
Follow the Manual
The success or failure of
this liftgate to properly and efficiently operate depends
on an ongoing preventative maintenance program.
Failure to read, understand, and follow the maintenance
instructions and safety recommendations in this manual
can result in serious injury or death.
Also, read and understand the operating instructions in
the separate Operation Manual before performing any
maintenance.
1.3 State and Federal Regulations
1.3.1 Lighting
WARNING If any lighting is installed or
changed, it must not alter or
prevent vehicle compliance with
any existing State or Federal standards such as FMVSS
108 – Lamps, Reflective Devices, and Associated
Equipment.
1.3.2 Rear Impact Guards
WARNING When stored in the transport
position, this liftgate must provide
protection against rear impact and
comply with State and Federal standards in your area.
Anthony Liftgates offers a bolt-on bumper, which meets
the requirements of this standard.
1.4 If Maintenance Help is Required
1.4.1 Maintenance (Dealer)
For additional information on installation, refer to the
website www.anthonyliftgates.com. To nd the most current
version of the reference material, choose LIFTGATES,
CONVENTIONAL, AC.
If you have any doubts or questions about the safe
installation of this liftgate, call us. Before doing so, have
the serial number, model number, and lift capacity of your
liftgate available.
Anthony Liftgates, Inc.
1037 West Howard Street
Pontiac, Illinois 61764
[phone] or 800-482-0003
1.4.2 Customer Service and Parts (End User)
For service or ordering replacement parts, contact an
authorized dealer by going to www.anthonyliftgates.com
and selecting the FIND A DEALER tab. Enter your zip code
to nd the nearest authorized service location.
N
I
NG
AR Being unaware of safety recommendations can
lead to personal injury. The user must make sure
all decals are attached to the liftgate and truck and
are legible.

1.5 Registration
Refer to the Operation Manual for the serial number
information.
1.6 Warranty
For a detailed copy of the Warranty Statement, refer to
the Operation Manual. To make an online warranty claim,
go to www.anthonyliftgates.com and select CUSTOMER
SERVICE and then select WARRANTY CLAIM.
Before calling with questions or other product information
requests, have the serial number, model number, and
lift capacity of the liftgate available. This information is
stamped into the identication plate on the side of the
adapter frame tube.
NOTICE The liftgate must be maintained
according to these instructions or the
warranty will be void.
ALI-00418
Common location for product information on an Anthony Liftgates liftgate.
1. Unauthorized modifications may cause improper
operation or other unforeseen problems or dangers. If
any deviation is deemed necessary, written permission
must be obtained from Anthony Liftgates.
2. All decals must be attached and legible, or all
warranties are void.
2. Safety
2.1 Safety is Your Responsibility
It is the responsibility of the maintenance personnel to
understand proper operating procedures. Be aware of the
inherent dangers in the use of this product and the tools
used to maintain it. Read and understand all Warnings,
Cautions, Notices, Safety Instructions, and Notes in this
manual, on the liftgate, or on the truck.
Accidents can often be avoided by being alert and
recognizing potentially hazardous situations. The safety
information in this manual serves as a basic guide in an
attempt to prevent injury or death.
Anthony Liftgates cannot anticipate every possible
circumstance that might involve a potential hazard. The
warnings in this manual and on the product itself are,
therefore, not all-inclusive. If tools, procedures, work
methods, or operating techniques are used that are not
specically mentioned by Anthony Liftgates, you must
satisfy yourself that they are safe for you and for others.
DO NOT proceed with any maintenance procedure if doubt
arises about the correct or safe method of performing any
procedure found in this manual. If you have any doubts or
questions about installation, call your authorized dealer.
Safety Signal Words
Personal injury hazards are identied by the “Safety
Alert Symbol” and followed by a signal word such as
WARNING or CAUTION to indicate the severity of
the hazard.
This safety alert icon surrounds an image showing a
specic type of injury which should be avoided.
These icons are shown on page 3.
WARNING
Indicates a potentially hazardous
situation which, if not avoided,
COULD result in death or serious
injury.
CAUTION
Indicates a potentially hazardous
situation which, if not avoided,
MAY result in minor or moderate
injury.
NOTICE
Indicates that equipment or property
damage can result if instructions are
not followed.
SAFETY
INSTRUCTIONS
Indicates specific safety-related
instructions or procedures.
Note: Contains additional information important to a
procedure.

2.2 Safety Icons Nomenclature
This manual and the equipment have numerous safety
icons. These safety icons provide important operating
instructions, which alert you to potential personal injury
hazards.
2.2.1 Personal Protection/
Important Information
Read the manual
Eye protection
Face shield / welding
helmet
Breathing protection
Head protection
Protective shoes
Hand protection
Use two people when lifting
heavy objects
Use proper tools
Weight rating
Set parking brake
Remove key
Lockout / prevent use
Properly installed parts
OEM
OEM
OEM parts
N
I
NG
AR
Damaged safety sign
2.2.2 Prohibited Actions
Do not alter or modify
Do not weld
No smoking
No open flame
No alcohol
No drugs
2.2.3 Hazard Avoidance
Safety alert symbol
Slipping injury
Tripping injury
Pinch point hazard
Pinch hazard (foot)
Dangerous fumes
Adequate ventilation
Crush hazard
Crush hazard
Crush hazard (chock
wheels)
Chock wheels /rollover
hazard
Fall hazard (truck)
Fall hazard (platform)
Damaged parts hazard
Fire hazard
Sparks / fire hazard
Battery gas hazard
2.3 Safety Rules
2.3.1 Personal Protection
WARNING Do not work under the lift-
gate while it is in a raised
position. Unintentional low-
ering of the liftgate can cause serious crushing injuries.
CAUTION
When servicing this unit, wear appropriate personal
protective equipment. This list may include, but is not
limited to:
• A hard hat.
• Protective shoes with slip resistant soles.
• Protective goggles, glasses, or face shield.
• Protective clothing.

CAUTION Anthony Liftgates
recommends not
riding the liftgate;
however, if the operation requires it, make sure your
footing is stable before raising or lowering the platform.
Always stand away from the edge. When on the ground,
always stand clear of the liftgate when it is operating.
Do not attempt to maintain the liftgate
under the influence of drugs or alcohol.
Consult your doctor before using the
liftgate while taking prescription medications.
To prevent personal injury, clean up any
spilled fluids immediately. To avoid
tripping, do not leave tools or components
laying around in the work area.
Failure to prevent the truck from moving
during the maintenance of the liftgate
could result in a serious crushing injury.
Always use/set the truck’s parking brake
and remove the ignition key before
servicing the liftgate. Failure to follow this
recommendation can result in injury.
Do not place hands or feet in pinch points.
Do not place your feet under the liftgate or
between the platform and floor extension.
To prevent injury, the liftgate and its related
components should only be maintained by a
qualified installer having knowledge and skill in
using a lifting device, a cutting torch, and welding
equipment.
N
I
NG
AR To prevent possible injuries due to improper
operation, make sure all decals are attached to
the liftgate and/or truck and are legible at all
times.
2.3.2 Equipment / Tools / Parts
CAUTION Do not operate this unit if
it is damaged. If you
believe the unit has a
defect, which could cause it to work improperly, you
should immediately stop and remedy the problem
before continuing.
Make sure the liftgate or truck will not be
damaged or made unsafe by the maintenance or
use of the liftgate.
Never secure the power cable to anything which
allows it to contact sharp edges, other wiring,
fuel tank, fuel lines, brake lines, air lines, exhaust
system, or any other object that could cause the power
cable to wear or be damaged. A cut battery cable can
cause sparks and/or component damage resulting in
loss of vehicle control, serious injury, or even death.
CAUTION OEM
OEM
If replacement parts are
necessary, genuine factory
OEM replacement parts
must be used to restore the liftgate to the original
specifications. Anthony Liftgates will not accept
responsibility for damages as a result of using
unapproved parts. If non-OEM replacement parts are
used, the warranty will be voided.
2.3.3 Battery / Fuel Tank Safety
WARNING To prevent
serious bodily
injury, keep
sparks, lighted matches, and open flames away from
the top of the battery because battery gas can explode.
Always follow all the manufacturers’ safety
recommendations when working around the truck’s
battery.
Take precautions to avoid sparks coming into
contact with the truck’s fuel tank, brake lines, or
other flammable components. Sparks can cause
an explosion of combustible materials, resulting in
serious injury or death.
2.3.4 Cutting Torch / Welding Safety
WARNING Take precautions to avoid
sparks from contacting the
truck’s fuel tank, brake
lines, or other flammable components. Sparks can
ignite combustible materials, resulting in serious injury
or death.
Always weld or use a cutting torch
in a well-ventilated area and, if in an
enclosed area, vent the fumes to
the outside. Breathing welding smoke and paint fumes
can cause serious injury.
Always follow all State and Federal health and
safety laws and/or local regulations when using an
arc welder, mig welder, or cutting torch. Also,
follow all manufacturers’ safety guidelines. If other people
are present during the installation of the liftgate, make
sure the assembly area is shielded from their view.
To avoid eye injury during welding, always wear
a welding helmet with the proper lens to protect
your eyes.
To avoid eye injury while using a cutting torch,
always use eye protection with the proper lens to
protect your eyes.
SAFETY
INSTRUCTIONS
Do not modify safety
devices. Do not weld
on the liftgate
assembly, except the adapter frame tube. Unauthorized
modifications may impair its function and safety.
Make sure all parts are in good working condition
and properly installed. Replace any damaged
parts immediately.

2.4 Welding or Grinding Galvanized or Stainless
Steel Material
2.4.1 Galvanized Metal
CAUTION
Follow all OSHA and other workplace safety standards
when welding galvanized steel, which creates zinc
oxide fumes. Always grind the coating off in the area to
be welded and provide adequate ventilation to avoid
breathing the fumes.
Always wear proper breathing protection when grinding
or welding. Use ventilation or vacuum systems to
remove any contaminated air from the work area.
Metal Fume Fever:
When zinc vapor mixes with the oxygen in the air,
it reacts instantly to become zinc oxide, which is
non-toxic and non-carcinogenic.
Zinc oxide that is inhaled is absorbed and eliminated
by the body without complications or chronic
effects.
Exposure to zinc oxide fumes causes a flu-like
illness called metal fume fever.
Symptoms include headache, fever, chills, muscle
aches, nausea, vomiting, weakness, and tiredness.
There are no long-term health effects. Metal fume
fever typically begins about four hours after
exposure, and full recovery occurs within 48 hours.
2.4.2 Stainless Steel
Follow all OSHA and other workplace safety standards
when welding stainless steel, which creates hexavalent
chromium fumes that can irritate the nose, throat, and
lungs.
Repeated or prolonged exposure can damage the
mucous membranes of the nasal passages and result
in ulcers. In severe cases, exposure causes perforation
of the septum (the wall separating the nasal passages).
Always wear proper breathing protection when grinding
or welding. Use ventilation or vacuum systems to
remove any contaminated air from the work area.
3. Nomenclature
3.1 Liftgate Nomenclature
Pump BoxMounting
Plate
Tubular Bumper
Attachment Brackets
Tubular Bumper
Attachment (optional)
Informational
Packet
Lift Frame
Adapter Frame
Tube
Transport
Latch Pin
Radius Arm
860
Platform

3.2 Gravity-Down Power Unit Nomenclature
861
Breather
Tube
Hydraulic
Cylinder
Power Up
High-Pressure
Hose
Flow Control
Valve
Control
Switch
Control
Box Wiring
Electric
Motor
Pump
Adjustable Relief
Valve
Motor Start
Solenoid
Power Up
(Raising Valve)
Cartridge
and Solenoid
Fill Port and
Breather
Cap
Reservoir
10 Amp In-Line Fuse
(BLACK wire)
(WHITE wire)
(GREEN wire) Power Cord w/
200 Amp Fuse
3.3 Power-Down Power Unit Nomenclature
370
Power Cord w/
200 Amp Fuse
Hydraulic
Cylinder
Control
Switch
Electric
Motor
Power DOWN
Valve
Power UP
Valve
Fill Port and
Breather
Cap
Reservoir
Power Up
High-Pressure
Hose
Flow Control
Valve
Power Down
High-Pressure
Hose
Motor Start
Solenoid
Pump
Adjustable
Relief
Valves
Control
Box Wiring
10 Amp In-Line Fuse
(BLACK wire)
(WHITE wire)
(RED wire)
(GREEN wire)

4. Maintenance
4.1 Monthly Inspection
All Anthony Tuckunder Liftgates are “Service-Free” which
means they have lubrication-free bushings at the major
pivot points.
Mechanical Components
1. Make sure the liftgate operates freely and smoothly
throughout its entire range of movement.
2. Check for damage to the liftgate, such as bent or
distorted parts. Check for excessively worn parts.
3. Check for cracked welds which may have resulted from
overload or abuse.
4. Check all pins and pivot points. Secure all pins with
proper retainers. Replace worn bushings and pins.
5. Oil the roller of the wheel arm and make sure it spins
freely.
6. Make sure the platform is angled upward from truck bed
1/2 to 3/4 inch when raised to bed height.
Power Unit
1. Check for oil leaks in the following areas:
a. Hydraulic lift cylinder.
b. Hydraulic hoses. Replace any hose that shows
signs of leakage or excessive abrasion of the
covering.
c. Check all hydraulic fittings for damage or leakage.
Tighten fittings to stop leaks or replace if damaged.
2. Check reservoir oil level. Refer to section “4.3 Check
Power Module Fluid Level” on page 10. Fill as
required with Hyken Glacial Blu.
NOTICE
To prevent damage to the pump,
use only the recommended Hyken
Glacial Blu anti-wear, low-viscosity,
hydraulic fluid in the power unit reservoir.
In an emergency, use any anti-wear hydraulic fluid, but
flush the system and replace it with our recommended fluid
soon as reasonably possible. Do not mix hydraulic oil and
automatic transmission fluid due to possible compatibility
problems.
Use the appropriate viscosity of fluid based on the
surrounding climate conditions. Viscosity is important
because the pump will not cause a temperature increase to
the oil in the reservoir, like a typical closed-loop hydraulic
system.
DO NOT use brake fluid in place of our recommended fluids.
Electrical Components
1. Make sure all electrical wires, switches, and
connections are in good working condition and operate
properly.
2. Proper wire connection is crucial to the life and
dependability of the liftgate’s electrical components. A
poor connection can result in low Voltage, causing the
liftgate to work incorrectly.
3. Check the fluid level of the vehicle battery.
Safety Signs and Informational Decals
1. Examine all warning, capacity, and operational decals.
If they are not readable, replace them. Decals may be
obtained free of charge your authorized dealer.
4.2 Semi-Annual Inspection
In addition to the items requiring monthly inspection, also
inspect the condition of the hydraulic uid.
If the oil in the hydraulic tank is dirty, drain the oil and ush
the entire system. Rell the system with the recommended
oil outlined in Step 8 of the “Monthly Inspection” section.
4.3 Check Power Module Fluid Level
Power Down Models: Check the fluid level with the
platform fully raised. The oil level should be approximately
1 inch below the filler cap.
1”
ALI-00613a
Gravity Down Models: Check the fluid level with the
platform resting on the ground. The oil level should be a
maximum of 1 inch from the top of the reservoir.
1”
NOTICE To prevent damage to the pump, use
only the recommended Hyken Glacial
Blu anti-wear, low-viscosity, hydraulic
fluid in the power unit reservoir.

In an emergency, use any anti-wear hydraulic fluid, but
flush the system and replace it with our recommended fluid
soon as reasonably possible. Do not mix hydraulic oil and
automatic transmission fluid due to possible compatibility
problems.
Use the appropriate viscosity of fluid based on the
surrounding climate conditions. Viscosity is important
because the pump will not cause a temperature increase to
the oil in the reservoir, like a typical closed-loop hydraulic
system.
DO NOT use brake fluid in place of our recommended fluids.
4.4 Power Cable Fuse - 200 Amp
CAUTION To avoid injury or property damage,
disconnect the liftgate’s power cable
from the battery before starting to
replace the fuse. An ”arc” can occur, resulting in personal
injury or property damage if the power cable is connected
to the battery.
200A
200A
200A
200A
1. Cut the heat shrink tube to expose the fuse, mounting
hardware, and lugs.
2. Remove the bolt, washer, and lock washer from each
end of the fuse.
3. Use the A-133610, 200 Hi-Amp Fuse Replacement Kit
for the replacement parts.
4. Slide the new heat shrink tube over one side of the
wiring.
5. Bolt the new fuse to the cable lugs using the bolts,
washers, and lock washer, as shown.
6. Slide the heat shrink tube over the fuse, hardware, and
lugs. Using a heat gun apply heat evenly to shrink the
tubing.
7. Reconnect the power cable to the battery after you are
certain the platform area is clear.
Note: If the fuse continues to blow, contact your authorized
dealer.
4.5 Checking the Power Cable
To check for a defective power cable, run the motor directly
from a spare battery using jumper cables.
1. Remove the battery connection to the motor.
2. Connect the negative jumper cable (ground) directly to
the liftgate. Connect the positive cable to the terminal
on the motor start solenoid.
3. If the motor operates, the battery cable is defective and
should be replaced.
4.6 Checking Motor Start Solenoid and Power
Cut-off Solenoid
2
1
ALI-00592
Motor start solenoid.
2
1
ALI-00695
Power cut-off solenoid.
Both the motor start solenoid and power cut-off solenoid
can be checked by bypassing the solenoid itself.
1. Use 12 Volt jumper cables for this test.
2. Connect one jumper cable to the battery side of the
solenoid. Connect the other cable to the motor side of
the solenoid.
3. If the liftgate is activated, the solenoid is defective and
should be replaced. Replacement part — ATU‑120 (motor
start solenoid) or A-150263 (power cut-off solenoid).

4.7 Checking Valve Cartridge and Solenoid
1. Place the liftgate on the ground in the open position.
2. Place a steel screwdriver over the top of the power
down valve solenoid.
593
3. Momentarily activate the control switch in the DOWN
position. The screwdriver should be attracted to the
magnetic field created by the solenoid.
4. Repeat the process to check the power up solenoid.
Momentarily activate the control switch in the UP
position.
5. If no magnetic pull is produced, the solenoid is defective
and should be replaced. If the solenoid is activated,
check the cartridge valve.
6. Remove the solenoid from the valve assembly.
Replacement part — A-176315.
7. Remove the valve cartridge from the pump body.
Replacement part — A-130216 (lowering valve) or
A-130215 (raising valve).
8. Clean the cartridge and blow it dry with compressed
air (not greater than 30 psi). Also, blow out the pump
body.
9. Use a small screwdriver and carefully press on the
spool inside the cartridge. If the spool moves freely,
the cartridge is good. If it does not move, replace
the cartridge, as the spool could be bent, pitted, or
damaged in some other way.
20a
4.8 Solenoid Valve Screen
29a
If the solenoid is working electrically, check the debris
screen and clean if dirty.
4.9 Replacing the Solenoid Valve
594
4
3
2
1
28a
1. While installed in the pump, remove nut (1).
2. Remove coil (2) from cartridge (3).
3. Remove cartridge (3) from pump body.
4. O-ring (4) is not required on current models and can be
discarded.

4.10 Checking Cylinder Piston Seals
4.10.1 Power Down Models
1. First, check the lowering valve. Make sure it is operating
correctly, and the valve is not sticking or dirty. Replace
the valve if necessary. Refer to “4.7 Checking Valve
Cartridge and Solenoid” on page 12.
2. Raise the platform approximately 12 inches off of the
floor.
3. Place a floor jack securely under the platform to support
its full weight. An overhead lifting device could also be
used.
4. Raise the floor jack until the platform begins to raise
slightly.
5. Disconnect the white wire from the motor start solenoid.
Place electricians tape around the end of the wire to
prevent it from making a ground connection.
White wire to
motor start
solenoid
759a
6. With the platform securely supported by the lifting
device, activate the control switch in the DOWN position
and hold the switch for 15 seconds. This will release
any pressure in the power down hose.
7. Now activate the control switch in the UP position and
hold it for 15 seconds. This will release any pressure in
the power up hose.
8. Repeat holding the control switch in the DOWN position
for 15 seconds and again in the UP position for 15
seconds. This should release any trapped pressure.
9. Carefully remove the flow control valve from the rod end
of the cylinder. Plug or cap the fitting.
10. Remove the hose from the cap end of the cylinder
and attach a temporary hose to catch any potential
leakage from the cylinder. Place the end of the hose in
a minimum one gallon container.
11. Lower the floor jack or lifting device.
12. Major seal damage will be apparent right away as
the platform would begin to slowly lower and fluid will
come out of the hose. Less extensive damage may
take longer to be seen. Allow the platform to sit for
several hours or overnight.
WARNING Make sure nothing or no
one could accidentally go
under the platform while the
hoses are disconnected.
13. If the platform does not lower, the seals are not the
problem, most likely it is a faulty lowering valve.
14. Reconnect the white wire to the motor start termial.
Raise and lower the platform several times to remove
any trapped air.
4.10.2 Gravity Down Models
1. Completely raise the platform.
WARNING Do not stand under the
platform.
2. Remove breather tube from the cap end of the cylinder
and attach a short piece of hose routed into a hand-
held container.
3. Activate the control switch in the UP position.
4. If oil is continuously pumped out of the hose, replace
the cylinder.
4.11 Checking System Pressure
For gravity down systems, there is only one relief valve
(power up). Power down models have two relief valve
settings; one for raising the platform (power up, upper
adjusting screw) and one for lowering the platform (power
down, lower adjusting screw).
To check the “power up” pressure setting:
1. Place the liftgate on the ground and remove the
pressure hose from the power up port of the pump.
725a
Power UP Model Pressure Hose Shown
2. Install a T-fitting (customer supplied) into the power up
port.
3. Connect a pressure gauge and reconnect the hydraulic
hose.
The pressure gauge must be rated above the maximum
pressure of the liftgate. For example, use a 4000
psi pressure gauge on a 3000 psi maximum capacity
liftgate.
4. Raise the liftgate and check the pressure on the gauge.

Low Pressure Threshold Chart
Model Power Up Power Down
1600 2800 psi
350 psi2000 2800 psi
2500 1850 psi
WARNING Do not stand or work in the
platform’s work area while
operating the liftgate. Place
the pressure gauge so it can be read while operating the
liftgate from a safe location. Serious injury or death
could result if this action is not followed.
5. To adjust the pressure, loosen the lock nut and
turn Allen screw clockwise to increase pressure or
counterclockwise to decrease the pressure. Retighten
locknut, and retest the pressure setting.
Note: To rest the pressure from zero, turn the adjusting
screw in all the way, then back out one full
turn. Retighten lock nut, test liftgate with load.
If liftgate performs well, set pump pressure
according to factory settings.
8
5
8
857
7
6. Check the “power down” relief valve pressure in the
same way as the “power up” by installing a T-fitting and
pressure gauge in the power down port.
4.12 Checking Flow Control Valve
856
If the cylinder does not operate or operates slower than
normal, remove the ow control valve and hook the
hydraulic hose directly to the cylinder. If the cylinder
operates properly, replace the ow control valve.
Replacement part — A-130102.
WARNING Do not operate the liftgate
without the flow control
valve. Serious injury or
death could result if this action is not followed.
4.13 Control Switch Fuse - 10 Amp
If the control switch is not operating the liftgate, check the
in-line fuse located on the control cable inside the power
unit box. Replace with A-150438 10A Fuse.
ALI-00596
ALI-00597

5. Troubleshooting Chart
Troubleshooting Chart
Problem Possible Causes Possible Solution
Motor does not run when
control switch is activated.
Cab cut‑off switch. Turn switch to ON position.
Replacement part — A‑150031
Optional power cut‑off solenoid. Check solenoid. “4.8 Checking Motor
Start Solenoid and Power Cut‑o
Solenoid” on page <?>.
Replacement part — A‑150263
Dead battery. Make sure battery is fully charged.
Check for loose or corroded battery
connections. Replace or recharge
battery.
Circuit protection (200 Amp fuse). Replace fuse. Refer to “4.6 Power Cable
Fuse ‑ 200 Amp” on page <?>.
Replacement part — A‑133610.
Control switch (10 Amp) fuse is blown. Replace the fuse inside power unit box.
If problem continues, check for shorts
in the electrical system. “4.15 Control
Switch Fuse ‑ 10 Amp” on page <?>
Replacement part — A‑150438.
Battery cable. Inspect main power cable from
batteries, to circuit breakers, to cut‑off
switch to power unit. To verify a faulty
cable, connect motor directly to a spare
battery using the procedure in the
Maintenance section.
Replacement part — A‑133604
Corroded or loose wire connections. Check all wire connections on power
unit for corrosion or looseness. Replace
defective terminals with ‘heat shrink’
factory type terminals.
Motor start solenoid. Check solenoid. “4.8 Checking Motor
Start Solenoid and Power Cut‑o
Solenoid” on page <?>.
Replacement part — ATU‑120.
Power unit motor. If the motor is determined to be
defective, it should be replaced.
Defective motors are typically caused
by weak batteries (low Voltage), loose
connections, corrosion, or a poor ground.
Replacement part — A‑150018
If the motor does not operate in
freezing conditions, make sure the
motor housing does not contain water.
Sagging platform. Normal wear. Add shims to platform. “4.5 Platform
Adjustment” on page <?>.
Replacement part — ATU‑071 SHIM, 14GA
Bushing wear where lift arms connect to
platform.
Replace bushings. Refer to separate
Parts Manual.
Structural damage. Replace worn parts. Refer to separate
Parts Manual.

Troubleshooting Chart
Problem Possible Causes Possible Solution
Foaming oil. Air in the hydraulic hose(s) or cylinder. Fill reservoir with proper fluid. Refer
to “4.1 Monthly Inspection” on page
<?> for oil specications and “4.3
Check Power Module Fluid Level” on
page <?> for oil level. Raise and lower
platform several times to remove any
trapped air.
Filter screen. Filter screen in pump reservoir is
damaged or plugged with dirt. Replace
filter screen.
Replacement part — A‑150016.
Broken or loose fluid return tube. Remove oil reservoir and make sure
return tube is below oil level. If tube
has turned or fallen out, reinstall it into
the pump housing. Use a center punch
to “stake” tube into position.
Replacement part — A‑150015
Motor runs, but liftgate will not open or
platform will not lower to the ground.
Structural damage. Check clearance
between platform and floor extension.
Fix damage. Replace worn parts. Refer
to the separate Parts Manual.
Latch pin. Slide the latch pin to the open position.
Lowering valve solenoid (power down
models only).
Check the solenoid. “4.9 Checking Valve
Cartridge and Solenoid” on page <?>.
Replacement part — A‑176315.
Lowering valve cartridge (power down
models only).
With platform on ground, check, remove,
and clean valve cartridge using the
procedure in section “4.9 Checking Valve
Cartridge and Solenoid” on page <?>. If
plunger will not move freely, replace.
Replacement part — A‑130216.
Cylinder seals. Cylinder piston seal are damaged
allowing fluid to leak past piston when
trying to raise platform. Replace the
cylinder, repair is not practical. Refer to
section “4.12 Checking Cylinder Piston
Seals” on page <?>.
Replacement part — A‑130113 Cylinder
3” or A‑130114 Cylinder 4”.
Flow control valve. Remove flow control valve and hook
hydraulic hose directly to the cylinder.
If the cylinder operates properly, replace
the valve. “4.14 Checking Flow Control
Valve” on page <?>.
Replacement part — A‑130102.
Latch pin is broken or bent. Operator has lowered platform without
releasing latch pin.
The latch pin is only used to prevent the
liftgate from opening due to a pressure
leak or pressure bleed‑off over an
extended period of time. Always release
latch before opening liftgate.
Platform raises truck when lowered to
the ground (power down models only).
Power down system pressure is set too
high.
See section “4.13 Checking System
Pressure” on page <?>.
Platform will not open. Platform operating area is not clear. Clear platform operating area.
Latch pin will not slide freely to release
liftgate.
Activate the “UP” switch and raise the
liftgate to the fully stored position.
The latch pin should slide freely.

Troubleshooting Chart
Problem Possible Causes Possible Solution
Motor runs, but platform will not raise,
will not raise rated capacity, or raises
but drifts down when control switch is
released.
Load capacity has been exceeded. Verify load capacity and reduce load
weight.
Structural damage. Replace damaged parts. Refer to the
separate Parts Manual.
Low fluid level. Fill reservoir with proper fluid. Refer to
“4.1 Monthly Inspection” on page <?>
for oil specications and “4.3 Check
Power Module Fluid Level” on page
<?> for oil level.
Low Voltage. Inspect the battery connection
terminals and check the battery’s
Voltage (9 Volts minimum).
Lowering valve (power down models
only).
Valve may not be fully closing. Cartridge
may need cleaning or replacement. See
section “4.9 Checking Valve Cartridge and
Solenoid” on page <?>.
Replacement part — A‑130216
Defective piston seals. Cylinder piston seals are damaged
allowing fluid to leak past piston when
raising platform. Replace the cylinder,
repair is not practical. Refer to section
“4.12 Checking Cylinder Piston Seals” on
page <?>.
Replacement part — A‑130113 Cylinder
3” or A‑130114 Cylinder 4”.
Hydraulic pump is worn. Replace power unit.
Replacement part — A‑130117 Power
Down or A‑130116 Gravity Down.
Platform raises partially and stops. Load capacity has been exceeded. Verify load capacity and adjust load
weight.
Structural damage. Replace damaged parts. Refer to the
separate Parts Manual.
Low Voltage. Recharge battery (if less than 9 Volts).
Low pressure. Fill reservoir with proper fluid. Refer to
“4.1 Monthly Inspection” on page <?>
for oil level and oil specications. Also
check pump and motor. “4.1 Monthly
Inspection” on page <?>.
Platform will not lower. Platform operating area is not clear. Clear area.
Structural damage. Replace damaged parts. Refer to the
separate Parts Manual.
Low Voltage. Recharge battery (if less than 9 Volts).
Lowering valve (power down models
only).
Solenoid or cartridge may need
cleaning or replacement. Refer to
section “4.9 Checking Valve Cartridge
and Solenoid” on page <?>.
Replacement part — A‑130216.
Hydraulic pump and motor. Replace power unit. Refer to the
separate Parts Manual.

Troubleshooting Chart
Problem Possible Causes Possible Solution
Platform lowers extremely slow. Low oil level on power down models. Fill reservoir with proper fluid. Refer to
“4.1 Monthly Inspection” on page <?>
for oil specications and “4.3 Check
Power Module Fluid Level” on page
<?> for oil level.
Improper oil in hydraulic reservoir. Fill reservoir with proper fluid. Refer to
“4.1 Monthly Inspection” on page <?>
for oil specications and “4.3 Check
Power Module Fluid Level” on page
<?> for oil level.
Bushing wear where lift arms connect to
platform.
Replace bushings. Refer to the separate
Parts Manual.
Damaged or kinked hydraulic hose. Repair or replace. Refer to the separate
Parts Manual.
Cylinder rod is scored, pitted, or bent. Replace the cylinder, repair is not
practical.
Replacement part — A‑130113 Cylinder
3” or A‑130114 Cylinder 4”.
Flow control valve. Remove flow control valve and hook
hydraulic hose directly to the cylinder.
If the cylinder operates properly, replace
the valve. “4.14 Checking Flow Control
Valve” on page <?>.
Replacement part — A‑130102.
Lowering valve (power down models
only).
Solenoid or cartridge may need
cleaning or replacement. Refer to
section “4.9 Checking Valve Cartridge
and Solenoid” on page <?>.
Replacement part — A‑130216.
Motor runs, but platform will not lift
stated load or drifts down after being
raised.
Low fluid level has caused air in the
lines.
Fill reservoir with proper fluid. Refer
to “4.3 Check Power Module Fluid
Level” on page <?> for oil level and
specications. Raise and lower the
platform several times to expel any
trapped air.
Lowering valve stuck in the open
position (power down models only).
With platform on ground, check,
remove, and clean valve cartridge using
the procedure in section “4.9 Checking
Valve Cartridge and Solenoid” on page
<?>. If plunger will not move freely,
replace. Replacement part — A‑130216.
Damaged cylinder piston seals. Refer to section “4.12 Checking
Cylinder Piston Seals” on page <?> for
additional information.
Relief valve is set too low or clogged
with contaminants.
Loosen locknut and turn Allen screw
clockwise to increase pressure.
Remove and clean if necessary.

6. Decals
SAFETY
INSTRUCTIONS
To prevent possible injuries
due to improper operation,
make sure all decals are
attached to the liftgate and truck and are legible.
1. Attach decals 1, 2, 3, 4, and 5 to the truck body, as
shown. If the truck is a flatbed, place the decals as
close to the control switch as possible and still clearly
visible.
891
NOTICE
THISLIFTGATE IS PROTECTED
WITHAN ELECTRICAL OVERLOAD
CIRCUITPROTECTION DEVICE,
EITHERA CIRCUIT BREAKER, OR
AFUSE, AND IS LOCATED NEAR
THEPOWER SUPPLY
A-150238
ATU-141
894
PERSONALINJURY HAZARD
Operationmay require userto stand on plat form.
Toprevent injuryor death of operators or bystanders:
Readand followoperator/owner manual for safety,
operation,inspection, and maintenance instructions.
•
Donotplace unstable or unsafe loads on plat form.
•
Donotallow loads to extend ov eredgeof platform.
•
Beawareof surroundings when operating liftgate.
•
Owner/operatorsmustproperly maintain li ftgate.
•
Ensurefooting is stable and stand away from edge
beforeraising orlowering platform.
•
Donotexc eedcapacityor use liftgate for anything
otherthan intended purpose.
•
Donotallow body parts to contact moving components.
•
WARNING
A-131115
03/2008
A-131020
MAXIMUM
CAPACITY
2000 lb.
1
2
3
4
5
2. Make sure factory-installed decals 6, 7, and 8 are
attached to the lift arms and platform.
892
A-150601
7
68
3. Make sure factory-installed decals 9, 10, 11, and 12
are installed on and inside the power unit and on the
adapter frame tube.
893
This hydraulic reservoir is
filled with Kendall Glacial Blu
hydraulic fluid. Use ONLY the
same or equivalent fluid.
A-131133
10AMP FUSE & HOLDER
Protectsagainst dead shorts
inthis "control circuit".
Ifblown, pull "fuse holder
cap",replace fuse, replace
"cap".If fuse continues to
blow,contact a qualified
mechanic,"control circuit"
maybe damaged.
A-131001
10AMP FUSE & HOLDER
Protectsagainst dead shorts
inthis "control circuit".
Ifblown, pull "fuse holder
cap",replace fuse, replace
"cap".If fuse continues to
blow,contact a qualified
mechanic,"control circuit"
maybe damaged.
12
9
10
11
Item
Part
Number Description
1 A-150238 Notice - Protected With Electrical Overload Circuit
Breaker
2 ATU-141 After Using Liftgate
3 A-131023 Operating Instructions
4 A-131115 Warning, Personal Injury
5
ATU-145
A-131020
ATU-174
1600 Lb. Maximum Capacity
2000 Lb. Maximum Capacity
2500 Lb. Maximum Capacity
6* A-131034 Anthony Label
7* A-131017 Note - Disengage Latch
8* A-150601 Made In The USA
9* A-131028 Weld Warning
10* A-131133 Hydraulic Fluid
11* A-131001 10 Amp Fuse Changing Procedure (attached to
control wiring in pump box)
12* A-131125 Warning, Galvanized Fumes Hazard (galvanized
models only)
*Factory Installed – Installer must make sure all decals are attached, as
shown.
1 — A-150238
2 — ATU-141

3 — A-131023
894
4 — A-131115
5 — ATU-145, A-131020, ATU-147
ATU-145
MAXIMUM
CAPACITY
1600 lb.
CAUTION Make sure the proper
“MAXIMUM
CAPACITY” decal is
placed on the truck for the appropriate lifting capacity
of the liftgate being installed. Do not put a higher rated
decal on a liftgate with a lower capacity; this could
result in liftgate damage or possibly personal injury.
6 — A-131034
7 — A-131017