B1A8A

B1A8A-00-MULTI-MODULE VIN HANDSHAKE FAILURE

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

- When Monitored:
During a Passive Entry or Keyless Go event.

- Set Condition:
The Radio Frequency Hub (RF Hub) receives and monitors the VIN messages from the Powertrain Control Module (PCM) and the Body Control Module (BCM). If the VIN is different from the last VIN it received, it will set this code. If the module was used on a previous vehicle, the VIN will be set to that vehicle.

- NOTE: Do not attempt to swap RF Hub modules. If a RF Hub module has been used on one vehicle, it cannot be used on another vehicle.





1. CHECK THE VEHICLE VIN
1. Turn the ignition on.
2. With the scan tool, select: "ECU Details".
3. Scroll down to "RF Hub", read the "VIN Original" and compare it to the actual vehicle VIN.

Does the RF Hub VIN Original match the vehicle VIN?

Yes

- Go To 2

No

- Go To 3

2. CHECK FOR ACTIVE DIAGNOSTIC TROUBLE CODE (DTC)
1. With the scan tool, record and erase the DTCs.
2. Turn the ignition off.
3. Wait five (5) minutes and then turn the ignition on.
4. With the scan tool, read the Active DTCs.

Does the scan tool display: B1A8A-00-MULTI-MODULE VIN HANDSHAKE FAILURE as active?

Yes

- Check the VIN numbers from the BCM and the PCM. If one of them does not match the vehicle VIN, using the scan tool in "Diagnostic Procedures", perform the "Reset ECU" procedure for that module. If it still does not match the vehicle, that module must be replaced.
- Replace the appropriate module.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

No

- Test complete, the condition or conditions that originally set this DTC are not present at this time. Check the history of this vehicle to see if the PCM or BCM were ever replaced. If one was, using the scan tool perform the "Reset ECU" procedure for that module.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

3. RESET ECU
1. With the scan tool go to the "Vehicle View" and select "Diagnostic Procedures".
2. With the scan tool, perform the "Reset ECU", "RFH" routine.
3. Turn the ignition off.
4. Try to start the engine three times.

Did the engine start?

Yes

- Test complete.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

No

- Replace the Radio Frequency Hub module. Radio Frequency Module (RF Hub) - Removal.
- Perform the RADIO FREQUENCY HUB VERIFICATION TEST. RF Hub Verification Test