Circuit Description
The Vehicle Theft Deterrent system (VTD) is incorporated within the Body Control Module (BCM). If the BCM has been replaced, the password must be relearned using approved Techline diagnostic equipment. If the PCM is replaced, the replacement PCM should learn the password within a few seconds after the ignition is turned ON. DTC P1630 is an information code indicating that the PCM is ready to learn the VTD password. The engine will start and continue to run with DTC P1630 set. Refer to Diagnostic System Check - Theft Deterrent for further information regarding the VTD system.
Conditions for Setting the DTC
| • | The VTD system has allowed fuel delivery. |
| • | The PCM is in the theft deterrent password learn mode. |
| • | The PCM remains in theft deterrent password learn mode for greater than 2 seconds. |
Action Taken When the DTC Sets
| • | The powertrain control module (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. |
| • | Interrupting the PCM battery voltage may or may not clear DTCs. This practice is not recommended. Refer to Powertrain Control Module Description , Clearing Diagnostic Trouble Codes. |
Diagnostic Aids
A new replacement PCM will be in a functional state to learn the password from the BCM. If the BCM is replaced, the PCM must be placed in password learning mode to relearn a new password. Once learned, the password becomes permanent information that remains with the vehicle. The loss of PCM battery or ignition voltage will not affect the programmed password information.
Refer to Diagnostic System Check - Theft Deterrent in Electrical Diagnosis for information concerning the password learning procedure.
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
1 | Did you perform the Powertrain On-Board Diagnostic System Check? | -- |
