B1A28

B1A28-ECM MISMATCH WITH SKIM





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

- When Monitored:
At ignition on or duraing any rolling code handshake that occurs with the Powertrain Control Module (PCM) due to a Wireless Control Module (WCM) or PCM reset.

- Set Condition:
If the WCM fails to receive a PCM STATUS message with a Valid Key status within 3.5 seconds of transmitting the last Valid Key Code message to the PCM.





1. VERIFY THAT THE DIAGNOSTIC TROUBLE CODE (DTC) IS ACTIVE

NOTE: Note: An external Radio-Frequency Identification (RFID) key (and/or pass/radio key) , such as one used to gain access to a 24 hour gym, can cause this DTC to set and create a no start condition. Inspect the customer's key chain for any type of RFID key. If one is not found, question the customer to see if a spare key chain has this RFID key on it or if it was removed from the original key chain before the vehicle was released for service. If a RFID key is present, remove the ignition key from the vehicle and remove the RFID key from the key chain. For GPEC equipped vehicles, disconnect the battery and wait a minimum of 5 minutes, reconnect and attempt to start the vehicle. For NCG equipped vehicles, turn the ignition on a minimum for one hour, and then attempt to start the vehicle. If the vehicle does not start, continue with the diagnostic test.

1. Turn the ignition on.
2. Using the scan tool, erase the WCM DTCs.
3. Turn the ignition off.
4. Wait 10 seconds.
5. Turn the ignition on and wait two minutes.
6. Using the scan tool, read the WCM DTCs.

Does the scan tool display the DTC that was previously erased?

Yes

- Go To 2

No

- Go To 4

2. VERIFY THAT THE PCM IS PROGRAMMED WITH THE CORRECT VIN
1. Using the scan tool, select ECU View, select PCM, select More Options, and select ECU Details.
2. Record the VIN displayed on the scan tool.

NOTE: Make sure that the proper Vehicle Identification Number (VIN) is programmed in the PCM. If the VIN does not display, attempt to program the PCM with the correct VIN before continuing.

Is the PCM programmed with the correct VIN?

Yes

- Go To 3

No

- Using the scan tool, perform PCM Replaced to update the VIN in the PCM.
- Perform the WCM VERIFICATION TEST. Wireless Control Module (WCM) Verification Test.

3. VERIFY THAT THE DTC IS ACTIVE
1. Turn the ignition off.
2. Replace and program the Wireless Control Module.
3. Turn the ignition on.
4. Using the scan tool, display and clear all PCM and WCM DTCs.
5. Perform five ignition key cycles leaving the ignition key on for 90 seconds per cycle.
6. Using the scan tool, check for WCM DTCs.

Does the scan tool display the same DTC?

Yes

- Replace and program the Powertrain Control Module.
- Perform the WCM VERIFICATION TEST. Wireless Control Module (WCM) Verification Test.

No

- The repair is complete.
- Perform the WCM VERIFICATION TEST. Wireless Control Module (WCM) Verification Test.

4. CHECK THE WIRE HARNESS FOR CAUSE OF INTERMITTENT CONDITION
1. Turn the ignition off.

NOTE: Check for the following conditions:
- Visually inspect the related wiring harness. Look for any chafed, pierced, pinched or partially broken wires.
- Visually inspect the related wiring harness connectors. Look for broken, bent, pushed out or corroded terminals.
- Perform any Technical Service Bulletins (TSB) that may apply.

Were any problems found?

Yes

- Repair wiring harness/connectors as necessary.
- Perform the WCM VERIFICATION TEST. Wireless Control Module (WCM) Verification Test.

No

- Test Complete.