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TROUBLSHOOTING
APRIL 2021
32DFR108.C
FR2SS-SERIES SERVICE MANUAL
TABLE 4-1: TROUBLESHOOTING GUIDE
Function
Symptom
Possible Cause
Remedy
STOW function
inoperative or er-
ratic (cont.)
Ramp stows very
slowly or stalls when
STOW/DEPLOY
switch is set to STOW
Sensor target requires
adjustment
Adjust sensor target; refer to section C.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 ful-
ly clockwise. Readjust valves as shown in s
Chap.2 section B.1.
Low hydraulic pres-
sure
▪
Check that hydraulic pump pressure out-
put is 1400 PSI. Adjust pump relief valve
as necessary.
▪
Check hydraulic lines for leaks or ob-
structions; 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 actua-
tor defective (binding
or jammed)
Replace hydraulic rotary actuator.
Ramp hinge or ramp
drive arms defective
(binding or jammed)
Repair or replace binding parts.
Hydraulic pump pres-
sure regulator defec-
tive
Replace hydraulic pump.
Hydraulic pump does
not shut off when
ramp is stowed
Hydraulic pump sole-
noid defective
Replace solenoid.
Hydraulic pump relay
defective
Replace relay.
Electronic controller
defective
Replace controller.
