Jacobsen Eclipse 322, Repair Manual

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ELECTRICAL
4222983 Second Edition 4-83
4
No Steering, No Fault: Traction Operational
1. Fault: Intermittent loss of steering with no fault(s) in
LDU or data log.
2. Possible root cause(s) and troubleshooting
procedure:
a. Low or no voltage into SCU. Measure VDC at B+
and B- at SCU while steering is not present
(must be in the seat.)
i. Low voltage could be caused by intermittent
or faulty 30 A circuit breaker in PDU.
Measure voltage in and out of 30 A circuit
breaker.
ii. Steering PCB relay faulty inside PDU.
Measure and compare voltage in and out of
steering relay.
iii. Faulty connection between PDU and SCU
(main harness). Measure and compare PDU
output to SCU B+.
iv. Steering controller disabled by TCU.
3. Fixes:
a. For issue 2.a.i: If circuit breaker is tripped, reset
and monitor. If low voltage is measured on the
other side of the breaker, then replace.
b. For issue 2.a.ii: Replace PDU.
c. For issue 2.a.iii: Correct connection issue.
d. For issue 2.a.iv: Repair TCU issue
4. If unit still does not operate after performing all the
above procedures, please contact Technical Support
immediately.
Fault: Miniscule Change in Steering Angle
without Operator Input (Ghost Steering)
1. Fault: Operator reports intermittent minimal steering
angle changes with no input to steering wheel. No
loss of steering or control.
2. Possible root cause(s) and troubleshooting
procedure:
• Noise inside the feedback optical signal between
steering input device (LORD) and SCU
3. Fixes:
• Call Technical Support for further information.
Steering Fault: 2310, 2340, 4210, 4310, 7310
1. Fault: Intermittent steering fault(s) with one of more
of the above codes recorded in the data fault log.
Fault(s) may not be displaying in LDU.
2. Possible root cause(s) and troubleshooting
procedure:
a. Feedback into SCU +5V signal ground could
cause erroneous steering faults
• Verify faults using data logger
b. Steer motor is faulty
• Correct ground wiring (Step 2.a) first. If fault
is still present, swap with known good
steering motor.
c. Steering motor wiring is damaged
• Visual inspection
• Verify proper motor orientation
3. Fixes:
a. For issue 2.a: Modify SCU +5VDU signal ground.
b. For issues 2.b and 2.c: Replace steering motor. If
issue is corrected, reinstall old steering motor to
verify fault returns.
4. If unit still does not operate after performing all the
above procedures, please contact Technical Support
immediately.