B2112
B2112-5 VOLT SUPPLY CIRCUIT LOW
For a complete wiring diagram, refer to the Wiring Information.
- When Monitored:
With the ignition on.
- Set Condition:
The Front Control Module (FCM) detects the (F891) 5 volt supply circuit voltage below 0.3 of a volt.
1. CHECK FOR ACTIVE DTC
1. Turn the ignition on.
2. With the scan tool, read the active DTCs.
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.
- Perform the BODY VERIFICATION TEST. Body Verification Test.
2. A/C PRESSURE TRANSDUCER
1. Turn the ignition off.
2. Disconnect the A/C Pressure Transducer harness connector.
3. Cycle the ignition switch from off to on, leaving the ignition on for a minimum of 90 seconds.
4. With the scan tool, read the active DTCs.
Does the scan tool display this DTC as active?
Yes
- Go To 3
No
- Replace the A/C Pressure Transducer.
- Perform the BODY VERIFICATION TEST. Body Verification Test.
3. (F891) 5 VOLT SUPPLY CIRCUIT SHORTED TO GROUND
1. Turn the ignition off.
2. Disconnect the FCM C1 harness connector.
3. 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 the BODY VERIFICATION TEST. Body Verification Test.
No
- Go To 4
4. (F891) 5 VOLT SUPPLY CIRCUIT SHORTED TO THE (C918) FCM SENSOR RETURN CIRCUIT
1. Measure the resistance between the (F891) 5 Volt Supply circuit and the (C918) FCM Sensor Return circuit.
Is the resistance below 1000.0 Ohms?
Yes
- Repair the (F891) 5 Volt Supply circuit for a short to the (C918) FCM Sensor Return circuit.
- Perform the BODY VERIFICATION TEST. Body Verification Test.
No
- Inspect the wiring and connectors for damage or shorted circuits. If OK, replace and program the Front Control Module.
- Perform the BODY VERIFICATION TEST. Body Verification Test.