DTC P1632
Diagnostic Instructions
DTC Descriptor
DTC P1632: Theft Deterrent Fuel Disable Signal Received
Circuit/System Description
The theft deterrent module (TDM) sends the fuel enable password to the engine control module (ECM) via the serial data circuit. The ECM then challenges this password. Both the ECM and TDM perform a calculation on this challenge. If the calculated response from the TDM equals the calculation performed by the ECM, the ECM will allow vehicle starting.
Conditions for Running the DTC
Ignition is in the RUN position.
Conditions for Setting the DTC
The calculated response from the TDM does not equal the calculation performed 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. |
Reference Information
Schematic Reference
Immobiliser Schematics
Connector End View Reference
Component Connector End Views
Description and Operation
Immobiliser Description and Operation
Electrical Information Reference
Scan Tool Reference
Control Module References for scan tool information
Circuit/System Verification
Note: 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 Control Module References
| ⇒ | 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
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