Anthony Liftgates AC-1600, Maintenance 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 specifications 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.