August 2021 Service and Repair Manual
Troubleshooting "HXXX" and "PXXX" Faults
Part No. 1309020GT GS
™
-30m • 32m • 30 • 32 • 46 • 55 183
Troubleshooting "HXXX" and "PXXX" Faults
The procedure below illustrates typical steps for diagnosing and fixing faults of type "HXXX" and "PXXX".
Diagnostic Chart
1
Check the faulted device for a short or open circuit.
No
Good
Replace faulted device.
Good
2
Check short or open circuit of the harness or
connector between Ground Controls and faulted device.
Good
Repair or replace harness an/or
connector.
Good
3
Check GCON Electronic Control Module (ECM).
No
Good
Replace ECM.
Wiring Diagram
The wiring diagram shown below illustrates how fault type "HXXX" and "PXXX" devices are typically
wired.
The signal of these types of devices originates at the Ground Controls and terminates at system ground.
GCON
Electronic Control Module
(ECM)
Signal Wire Signal Side Device Return Side Return Wire
In order to successfully troubleshoot "HXXX" or "PXXX" type faults, the entire faulted out circuit must be
investigated.