Diagnostic Aids
WARNING: This page is about a different variant/trim than selected.
DTC P1631 indicates that the vehicle theft deterrent password that the PCM has learned does not agree with password being received from the VTD system. This condition can occur is an incorrect key is being used when attempting to start vehicle or if BCM has been replaced and the PCM's password learn function has not been enabled.
If BCM has been replaced, the password must be relearned using special equipment.