B2112

B2112-5 VOLT SUPPLY CIRCUIT LOW (FCM)





For a complete wiring diagram Consult Diagrams/Electrical.

- When Monitored:
With the ignition on.

- Set Condition:
The Front Control Module detects the (F891) 5 volt supply circuit voltage below 0.3 volts.





Diagnostic Test

1. CHECK FOR ACTIVE DTC
With the scan tool, read the active DTC's.
Cycle the ignition switch from off to on, leaving the ignition on for a minimum of 90 seconds.
With the scan tool, read the active DTC's.
Does the scan tool display this DTC as active?

Yes

- Go To 2

No

- If the DTC is stored, check for an intermittent condition. Visually inspect the related wiring harness connectors. Look for broken, bent, pushed out, or corroded terminals.

2. A/C PRESSURE TRANSDUCER
Turn the ignition off.
Disconnect the A/C Pressure Transducer harness connector.
Cycle the ignition switch from off to on, leaving the ignition on for a minimum of 90 seconds.
With the scan tool, read the active DTC's.
Does the scan tool display this DTC as active?

Yes

- Go To 3

No

- Replace the A/C Pressure Transducer.
- Perform BODY VERIFICATION TEST - VER 1.Body Verification Test.

3. (F891) 5 VOLT SUPPLY CIRCUIT SHORTED TO GROUND




Turn the ignition off.
Disconnect the FCM C1 harness connector.
Measure the resistance between ground and the (F891) 5 Volt Supply circuit.
Is the resistance below 1000.0 ohms?

Yes

- Repair the (F891) 5 Volt Supply circuit for a short to ground.
- Perform BODY VERIFICATION TEST - VER 1.Body Verification Test.

No

- Inspect the wiring and connectors for damage or shorted circuits. If ok, replace and program the Front Control Module.
- Perform BODY VERIFICATION TEST - VER 1.Body Verification Test.