32DFR114.A
4 - 4
TABLE 4-1: TROUBLESHOOTING GUIDE
Function
Symptom
Possible Cause
Remedy
Sensor target requires
adjustment
Adjust sensor target; refer to section B.6 in
this chapter.
Hydraulic fluid level
low
Check hydraulic fluid level; refill as required.
Needle valve setting is
too restrictive
Close both needle valves by turning them
fully clockwise. Readjust valves as shown in
section C.5 in this chapter.
Low hydraulic
pressure
§
Check that hydraulic pump pressure
output is 1400 PSI. Adjust pump relief
valve as necessary.
§
Check hydraulic lines for leaks or
obstructions; Repair, as required.
§
Replace hydraulic pump.
Hydraulic pump wiring
harness defective
Repair or replace harness from electronic
controller to hydraulic pump.
Pump directional valve
defective
Replace hydraulic pump.
Hydraulic rotary
actuator defective
(binding or jammed)
Replace hydraulic rotary actuator.
Ramp hinge or ramp
drive arms defective
(binding or jammed)
Repair or replace binding parts.
Ramp stows very
slowly or stalls when
STOW/DEPLOY
switch is set to STOW
Hydraulic pump
pressure regulator
defective
Replace hydraulic pump.
Hydraulic pump
solenoid defective
Replace solenoid.
Hydraulic pump relay
defective
Replace relay.
STOW function
inoperative or
erratic (cont.)
Hydraulic pump does
not shut off when
ramp is stowed
Electronic controller
defective
Replace controller.
