Ignition System: Testing and Inspection

IGNITION RUN/START MISMATCH (FCM)

Ignition Run/Start Mismatch (FCM):

WHEN MONITORED
With the ignition on.

SET CONDITION
The FCM detects an ignition run/start mismatch.

POSSIBLE CAUSES
- Instrument cluster
- Power distribution center
- Front control module

Diagnostic Test

1. CHECK FOR AN ACTIVE DTC
Turn the ignition on.
With the DRB, erase the FCM DTC's.
Turn the ignition off then turn the ignition on and wait approximately 1 minute.
With the DRB, read the FCM DTC's.

Q: Did this DTC reset?

YES: Go To 2
NO: The condition that set this DTC is no longer present. Using the wiring diagram/schematic as a guide, inspect the wiring for chafed, pierced, pinched, and partially broken wires and the wiring harness connectors for broken, bent, pushed out, and corroded terminals.

2. CHECK THE STATUS OF THE INSTRUMENT CLUSTER

NOTE:
- Ensure the battery is fully charged before proceeding with this test.
- Diagnose and repair any Airbag, Instrument Cluster, or PCM DTCs before proceeding with this test.

With the DRB, select MIC, Monitors and observe the ignition state.
While observing the ignition state, start the vehicle.

Q: Does the DRB display run and start when the ignition switch is in those positions?

YES: Go To 3
NO: Replace and program the Instrument Cluster. Perform BODY VERIFICATION TEST - VER 1.

3. CHECK THE FUSED IGNITION SWITCH OUTPUT CIRCUIT

NOTE: Check IPM fuse #50 for an open before proceeding with this test.




Turn the ignition off.
Remove the FCM from the IPM. Turn the ignition on.
Using a 12-volt test light connected to ground, probe the Fused Ignition Switch Output circuit (cavity 48).

Q: Is the test light illuminated?

YES: Replace the Front Control Module. Perform BODY VERIFICATION TEST - VER 1.
NO: Replace the Power Distribution Center. Perform BODY VERIFICATION TEST - VER 1.