P1631

Diagnostic Chart (Part 1 Of 2):

Diagnostic Chart (Part 2 Of 2):

Schematic:

CIRCUIT DESCRIPTION
This test checks for mismatched passwords between the Vehicle Theft Deterrent (VTD) control module and Powertrain Control Module (PCM). Whenever the VTD control module or PCM are replaced, a theft learn procedure must be followed in order for the new password to be learned.

CONDITIONS FOR RUNNING THE DTC
The vehicle Anti-Theft system is enabled.

CONDITIONS FOR SETTING THE DTC
^ The fuel disable is set.
^ An incorrect fuel continue password has been received.

ACTION TAKEN WHEN THE DTC SETS
^ The vehicle will not start.
^ The Malfunction Indicator Lamp (MIL) will not illuminate.

CONDITIONS FOR CLEARING THE MIL/DTC
^ A history DTC clears after 40 consecutive warm-up cycles, if this or any other emission related diagnostic does not report any failures.
^ The scan tool Clear Info function was used.

TEST DESCRIPTION
The numbers below refer to the step numbers on the diagnostic table:
3. The 11 minute and 30 second time criteria, are minimum required amounts of time. Exceeding these limits will not interfere with the Auto Learn Procedure. A scan tool can be used to determine when the 11 minutes have expired. VTD Auto Learn Timer equals Inactive.
8. If DTC P1631 is set, the Re-Learn procedure was not performed correctly. The Re-learn procedure will then have to be repeated.