Description
The vehicle identification number (VIN) information is stored by the following devices:
| • | The engine control module (ECM) |
| • | The body control module (BCM) |
| • | The instrument panel cluster (IPC) |
The ECM reads the BCM VIN information every ignition cycle to verify a match between the two modules. If the ECM detects a VIN mismatch between the ECM and the BCM, this DTC will set.
Conditions for Running the DTC
| • | The ignition is ON. |
| • | There is no Class II serial data circuit condition. |
Conditions for Setting the DTC
The VIN programmed for the ECM and for the BCM do not match.
Action Taken When the DTC Sets
| • | The control module stores the DTC information into memory when the diagnostic runs and fails. |
| • | The malfunction indicator lamp (MIL) will not illuminate. |
| • | The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Failure Records. |
| • | The driver information center, if equipped, may display a message. |
Conditions for Clearing the DTC
| • | A current DTC Last Test Failed clears when the diagnostic runs and passes. |
| • | A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other non-emission related diagnostic. |
| • | Clear the DTC with a scan tool. |
Diagnostic Aids
| • | If an ECM or a BCM is exchanged from another vehicle, this DTC may set. |
| • | If the ECM is replaced and the new ECM is not programmed, or the ECM is incorrectly programmed, this DTC may set. Refer to Service Programming System (SPS) in Programming. |
| • | If both the ECM and the BCM are programmed with the correct VIN for the vehicle, clear the DTCs from both modules. |
Step | Action | Yes | No |
|---|---|---|---|
1 | Did you perform the Diagnostic System Check-Engine Controls? | Go to Step 2 | |
2 | Observe the vehicle identification number (VIN) for the engine control module (ECM) with a scan tool. Does the stored VIN match the vehicle? | Go to Step 4 | Go to Step 3 |
3 |
Does the stored VIN match the vehicle? | Go to Step 8 | Go to Step 7 |
4 | Observe the VIN for the body control module (BCM) with a scan tool. Does the stored VIN for the BCM match the stored VIN for the ECM? | Go to Diagnostic Aids | Go to Step 5 |
5 |
Does the stored VIN for the BCM match the stored VIN for the ECM? | Go to Step 8 | Go to Step 6 |
6 | Replace the BCM. Refer to Body Control Module Replacement in Body Control System. Did you complete the replacement? | Go to Step 8 | -- |
7 | Replace the ECM. Refer to Engine Control Module Replacement . Did you complete the replacement? | Go to Step 8 | -- |
8 |
Does the DTC fail this ignition? | Go to Step 2 | Go to Step 9 |
9 | Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed? | System OK |
