DTC Descriptor
DTC P1632: Theft Deterrent Fuel Disable Signal ReceivedDiagnostic Fault Information
Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
Circuit/System Description
The theft deterrent module (TDM) sends the pre-release password to the engine control module (ECM) via the serial data circuit. This pre-release password is an indicator that the vehicle key information as processed by the TDM is correct. If the vehicle key data is not correct, the TDM will send a fuel disable request to the ECM, indicating that vehicle starting should not be allowed. The ECM will disable engine starting at this point.
Conditions for Running the DTC
Ignition is in the ACCESSORY or RUN position.
Conditions for Setting the DTC
A fuel disable signal from the TDM is received by the ECM.
Action Taken When the DTC Sets
| • | The security indicator will illuminate. |
| • | Vehicle starting will be disabled. |
Conditions for Clearing the DTC
| • | A current DTC P1632 will be when a valid calculation is received. |
| • | A history DTC will be cleared after 40 malfunction free ignition cycles or when a scan tool is used to clear DTCs. |
Diagnostic Aids
The pre-release password sent to the ECM by the TDM is reliant on the communications between the transponder located in the vehicle key and the TDM. Failure to establish communications or an interruption in the communications between the vehicle key and the TDM will cause the fuel disable message to be sent and the setting of DTC P1632. In this instance, DTC B3055 or B3060 will be set in the TDM. To properly diagnose DTC P1632, DTC B3055 or B3060 must be diagnosed and corrected first.
Reference Information
Schematic Reference
Theft Deterrent System Schematics
Connector End View Reference
Theft Deterrent System Connector End Views
Description and Operation
Vehicle Theft Deterrent (VTD) Description and Operation
Electrical Information Reference
Scan Tool Reference
Circuit/System Verification
Important: Because of normal system communications between the TDM and ECM, any theft deterrent B-codes must be diagnosed prior to the diagnosis of P-codes.
Perform the Programming Theft Deterrent System Components procedure. Refer to Programming Theft Deterrent System Components . The ECM should successfully complete the password learn and the vehicle should start.
| ⇒ | If the ECM does not complete the learn or vehicle starting remains disabled, replace the ECM. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
Control Module References for ECM replacement, setup and programming.
