Test Procedure
NOTE:
Use this procedure if one or more of the LED segments will not display.
The "Self-Diagnostic System Check" is an organized approach for identifying a problem caused by the on-board computer controlled electronics. Understanding this chart and using it correctly will reduce diagnosis time and prevent the unnecessary replacement of parts.
NOTE:
The following step numbers refer to circled numbers on diagnostic chart. See Fig 1
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- This process assures that there are no BCM inputs active that would not allow the system to "Wake-Up" in the correct sequence. Are the IPC and COMBO Panel displays operating? If these displays are not operating, then the problem is related to power and ground circuits to the IPC, COMBO Panel, or BCM.
- Is the "Engine Control System Fault" telltale working? If this telltale fails to illuminate during crank, then the problem could be in the power supply circuits to the computer system.
- The odometer displays and "Engine Control System Fault" lamp work. Enter diagnostics and continue with code diagnosis. If diagnostics cannot be entered, refer PFI CHART C-1: ECM REPLACEMENT CHECK to in SELF-DIAGNOSTICS article in ENGINE PERFORMANCE. Is there a trouble code displayed? If a trouble code is identified using the self-diagnostics, a problem has been detected by the system which can be corrected following the appropriately numbered code chart.
- For CHART C-1, see C CHARTS (SYSTEM CHECK) .