P1632 (With RPO Y41)

DTC P1632 (with RPO Y41)

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (Initial Inspection and Diagnostic Overview) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Initial Inspection and Diagnostic Overview) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Initial Inspection and Diagnostic Overview)provides an overview of each diagnostic category.



DTC Descriptor
DTC P1632
- Theft Deterrent Fuel Disable Signal Received




Circuit/System Description

The remote control door lock receiver (RCDLR) sends the prerelease password to the engine control module (ECM) via the serial data circuit. The ECM then sends a challenge to the RCDLR. Both the ECM and RCDLR perform a calculation on this challenge. If the calculated response from the RCDLR 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

A fuel disable signal from the RCDLR 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 prerelease password sent to the ECM by the RCDLR is reliant on the communications between the transponder located in the vehicle key and the RCDLR. Failure to establish communications or an interruption in the communications between the vehicle key and the RCDLR will cause the fuel disable message to be sent and the setting of DTC B1632. DTC B3055 or B3060 will be set in the RCDLR. To properly diagnose DTC P1632, DTC B3055 or B3060 must be diagnosed and corrected first.


Reference Information
Schematic Reference

Immobilizer Schematics (Immobilizer Schematics)
Connector End View Reference

Component Connector End Views (Connector Views)
Description and Operation

Immobilizer Description and Operation (without RPO Y41) (Immobilizer Description and Operation (without RPO Y41))Immobilizer Description and Operation (with RPO Y41) (Immobilizer Description and Operation (with RPO Y41))
Electrical Information Reference

* Circuit Testing (Component Tests and General Diagnostics)
* Connector Repairs (Component Tests and General Diagnostics)
* Testing for Intermittent Conditions and Poor Connections (Component Tests and General Diagnostics)
* Wiring Repairs (Component Tests and General Diagnostics)

Scan Tool Reference

Control Module References (Programming and Relearning)for Scan Tool Information


Circuit/System Verification

Important: Because of normal system communications between the RCDLR and ECM, any theft deterrent B-codes must be diagnosed prior to the diagnosis of P-codes.



Perform the 10-Minute Immobilizer Relearn procedure. Refer to Immobilizer System Component Programming (without RPO Y41) (Programming and Relearning)Immobilizer System Component Programming (with RPO Y41) (Programming and Relearning) . 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 (Verification Tests) after completing the diagnostic procedure.


Control Module References (Programming and Relearning)for ECM replacement, setup and programming