Front Control Module (FCM)

B211B-IGNITION RUN/ACC/SPAD CONTROL CIRCUIT HIGH





For a complete wiring diagram, refer to the Wiring Information Electrical Diagrams.

Theory of Operation

The family of B2100 Diagnostic Trouble Codes (DTCs) typically describes ignition performance related faults. These are often caused by a contradiction of switch status information. For example, if an Electronic Control Unit (ECU) receives a bussed message indicating ignition switch position but the state of a hardwired ignition circuit indicates another switch position a B2100 series DTC would likely result.

These DTCs can be caused by a number of conditions including:

- loose connections
- missing or blown fuses
- faulty component
- vehicle no start or long crank time

Verify the proper operation of the starting system and verify that this DTC is active before proceeding with the diagnostic test.

- When Monitored:
With the ignition on.

- Set Condition:
The Front Control Module (FCM) will set this DTC within 500ms if the (W12) Rear Wiper Relay Control circuit is shorted to voltage.





1. CHECK FOR ACTIVE DIAGNOSTIC TROUBLE CODE (DTC)
1. Turn the ignition on.
2. Using 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. (W12) REAR WIPER RELAY CONTROL CIRCUIT SHORTED TO VOLTAGE




1. Turn the ignition off.
2. Disconnect the Junction Block C1 harness connector.
3. Disconnect the IPM C2 harness connector.
4. Turn the ignition on.
5. Measure the voltage of the (W12) Rear Wiper Relay Control circuit at the Junction Block C1 harness connector.

Is the voltage above 10.0 Volts?

Yes

- Repair the (W12) Rear Wiper Relay Control circuit for a short to voltage.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

No

- Go To 3

3. (W12) REAR WIPER RELAY CONTROL CIRCUIT SHORTED TO GROUND




1. Turn the ignition off.
2. Reconnect the IPM C2 harness connector.
3. Remove the FCM from the IPM.
4. Turn the ignition on.
5. Measure the voltage of the (W12) Rear Wiper Relay Control circuit at the Junction Block C1 harness connector.

Is the voltage above 10.0 Volts?

Yes

- Replace the IPM.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

No

- Replace the FCM.
- Perform the BODY VERIFICATION TEST. Body Verification Test.