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TROUBLSHOOTING
APRIL 2021
32DFR108.C
FR2SS-SERIES SERVICE MANUAL
IV. FOLDOVER RAMP TROUBLESHOOTING
he troubleshooting information in this chapter applies to the Ricon FoldOver Stainless Steel Low-Floor Vehicle
Access ramp when installed in transit vehicles. It provides two troubleshooting guides, one in table format, the
other in flowchart format. The table guide covers several possible failure modes, including complete lack of re-
sponse, erratic behavior, and inability to stow. The flowchart commences with the general symptom of no ramp re-
sponse, and then follows a step-by-step procedure to check all possible causes of this symptom. Use the electrical wir-
ing diagrams in Figures 3-12, 3-13 and 3-14
along with the hydraulic diagrams in
Figures 3-9, 3-10 and 3-11 of Chapter
III to supplement this chapter.
NOTE:
Some applications require 12 VDC system power. Where this applies, voltage levels are 12 VDC.
A. TROUBLESHOOTING TABLE
TABLE 4-1: TROUBLESHOOTING GUIDE
Function
Symptom
Possible Cause
Remedy
DEPLOY
function in-
operative or
erratic
Hydraulic pump does
not operate; pump so-
lenoid does not oper-
ate
Main circuit breaker
tripped
Reset circuit breaker.
Hydraulic pump circuit
breaker tripped
Reset circuit breaker.
Vehicle battery charge
too low
Check vehicle battery. If necessary, operate
ramp with vehicle engine running.
No power to ramp har-
ness connector pin
P1-6 (blue lead)
Check for input power at ramp harness connect-
or pin P1-6. Repair wiring, as required.
No signal from switch
to ramp harness con-
nector pin P1-5 (black
lead)
Check for deploy signal at ramp harness con-
nector pin P1-5. Repair wiring, as required.
STOW/DEPLOY
switch defective
Replace or repair STOW/DEPLOY switch.
Door switch interlock
circuit defective
Replace or repair door switch.
Main ramp power
switch defective
Replace or repair main ramp power switch.
Pump solenoid defec-
tive
Replace pump solenoid.
Pump relay defective
Replace pump relay.
Electronic controller
defective
Replace controller.
Deploy sensor is de-
fective or out of ad-
justment
Adjust ramp sensor target; set proper sensor-to-
target distance; refer to Chap.2 section B.2. Re-
place sensor, if necessary.
Hydraulic pump assy
wiring harness defec-
tive
Check wiring harness to hydraulic pump assem-
bly. Repair wiring, as required.
Pump solenoid oper-
ates, but no ramp
movement occurs
Flow control valves are
closed
Adjust valves as shown in Chap.2 section B.1.
Flow control valves are
clogged
Clean the valves. Adjust valves as shown in
Chap.2 section B.1.
Air in hydraulic system
Cycle ramp to bleed system. Refill hydraulic fluid
reservoir as required.
T
