P1631

Circuit Description
This test checks for mismatched passwords between the BCM and PCM. Whenever replacing the BCM or PCM, follow the theft learn procedure in order for the system to learn the new password.

Conditions for Running the DTC
Mismatched passwords between the BCM and PCM

Conditions for Setting the DTC
^ The PCM detects a wrong password from the BCM.
^ Fuel disable lockout is set.
^ The system has received an incorrect fuel continue password.
^ A faulty ignition switch.
^ The BCM was replaced.

Action Taken When the DTC Sets
^ The engine starts and then the engine stalls immediately.
^ The PCM stores the DTC information into memory when the diagnostic runs and fails.
^ The Malfunction Indicator Lamp (MIL) will not illuminate.
^ The PCM records the operating conditions at the time the diagnostic fails. The PCM stores this information in the Failure Records.

Conditions for Clearing the MIL/DTC
^ A History DTC will clear after forty consecutive warm-up cycles, if no failures are reported by this or any other non-emission related diagnostic.
^ A last test failed (Current DTC) will clear when the diagnostic runs and does not fail.
^ Use a scan tool in order to clear the MIL/DTC.

Test Description
The numbers below refer to the step numbers on the diagnostic table.
3. The 11 minute and 30 second time criteria are a minimum required amount of time. The time limit can exceed this limit without interfering with the Auto Learn Procedure. Use a scan tool (VTD Auto Learn Timer equals Inactive) in order to determine when the 11 minutes has expired.
6. If DTC P1631 is set, this indicates that you did not follow the procedure correctly. Perform the Re-learn procedure again.