Pinpoint Test W: The Mil (Malfunction Indicator Lamp) Is Never Or Always On
- Normal Operation and Fault Conditions
See MIL. REFER to: Instrument Panel Cluster (IPC) - System Operation and Component Description .
If the MIL request message is missing or invalid for less than 5 seconds, the IPC defaults the MIL to its last state (on or off) based upon the last known good message received.
If the MIL request message is missing for 5 seconds or longer, the IPC defaults the MIL on.
Possible Sources
- Communication concern
- GWM concern
- PCM
- IPC
- W1 PERFORM THE IPC (INSTRUMENT PANEL CLUSTER) SELF-TEST
- Ignition ON.
- Using a diagnostic scan tool, perform the IPC self-test.
Are any Diagnostic Trouble Codes (DTCs) recorded?
Yes REFER to DTC Chart: Instrument Panel Cluster (IPC) . No GO to W2 - W2 PERFORM THE PCM (POWERTRAIN CONTROL MODULE) KOEO (KEY ON, ENGINE OFF) SELF-TEST
- Using a diagnostic scan tool, perform the PCM KOEO self-test.
Are any Diagnostic Trouble Codes (DTCs) recorded?
Yes REFER to the appropriate Electronic Engine Controls article. No GO to W3 - W3 CHECK THE GWM (GATEWAY MODULE A) DIAGNOSTIC TROUBLE CODES (DTCS)
- Using a diagnostic scan tool, check the GWM Continuous Memory Diagnostic Trouble Codes (CMDTCs).
Are any Diagnostic Trouble Codes (DTCs) recorded?
Yes REFER to: Communications Network No GO to W4 - W4 PERFORM THE IPC (INSTRUMENT PANEL CLUSTER) INDICATOR LAMP CONTROL ACTIVE COMMAND USING A DIAGNOSTIC SCAN TOOL
- Using a diagnostic scan tool, view the IPC Parameter Identifications (PIDs).
- Select the IPC (MIL) PID.
- Command the MIL on and off while observing the indicator.
Does the MIL illuminate when commanded on and turn off when commanded off?
Yes If the MIL is always on, Refer to PCM Guided Routine .
If the MIL is never on, the system is operating correctly at this time.No INSTALL a new IPC. Refer to Instrument Panel Cluster (IPC) .