3C Run/Start Hardwire Input Mismatch
3C-RUN/START HARDWIRE INPUT MISMATCH
- When Monitored:
Continuously.
- Set Condition:
When the BCM detects the Run-Start circuit is not active but the MUX switch is in the Run position for 2 seconds.
1. CHECK PDC FUSE C4
NOTE: Diagnose and repair any Ignition MUX DTCs before proceeding with this test.
1. Turn the ignition off.
2. Check fuse C4 in the PDC
Is the fuse open?
Yes
- Using the wiring diagrams as a guide, repair the (G5) Fused Ignition Switch Output (Run/Start) circuit for a short to ground.
No
- Go To 2
2. (A1) FUSED B(+) CIRCUIT OPEN
NOTE: Diagnose and repair any Ignition MUX DTCs before proceeding with this test.
NOTE: Check Fuse B10 in the PDC. If open, view repair.
1. Turn the ignition off.
2. Disconnect the Ignition Switch harness connector.
3. Measure the voltage between the (A1) Fused B(+) circuit and ground.
Is the voltage above 10.0 volts?
Yes
- Go To 3
No
- Repair the (A1) Fused B(+) circuit for an open. If the fuse is open, check for a short to ground.
- Perform the BODY VERIFICATION TEST. Body Verification Test.
3. IGNITION SWITCH
1. Turn the ignition off.
2. Reconnect the Ignition Switch harness connector.
3. Turn the ignition on.
4. While back probing at the ignition switch, measure the voltage of the (A21) Fused Ignition Switch Output (Run-Start) circuit.
Is the voltage above 10.0 volts?
Yes
- Go To 4
No
- Replace the Ignition Switch.
- Perform the BODY VERIFICATION TEST. Body Verification Test.
4. (A21) IGNITION SWITCH OUTPUT (RUN-START) CIRCUIT OPEN
1. Turn the ignition off.
2. Disconnect the BCM C4 harness connector.
3. Disconnect the Ignition Switch harness connector.
4. Measure the resistance of the (A21) Ignition Switch Output (Run-Start) circuit between the BCM C4 connector and the Ignition Switch connector.
Is the resistance above 5.0 Ohms?
Yes
- Repair the Fused Ignition Switch Output (Run-Start) circuit for an open. If the fuse is open make sure to check for a short to ground.
- Perform the BODY VERIFICATION TEST. Body Verification Test.
No
- Replace and program the Body Control Module.
- Perform the BODY VERIFICATION TEST. Body Verification Test.