2010 Cadillac Truck SRX FWD V6-3.0L Page 1630
Diagnostic Aids
The key referenced in the DTC descriptor does not refer to the vehicle key. In this case, key is referring to the challenge response.
Reference Information
Schematic Reference
Immobilizer Schematics (See: Accessories and Optional Equipment/Antitheft and Alarm Systems/Diagrams/Electrical Diagrams/Immobilizer
Schematics)
Connector End View Reference
Component Connector End Views (See: Diagrams/Connector Views/Connector End Views By Name)
Description and Operation
Immobilizer Description and Operation (See: Accessories and Optional Equipment/Antitheft and Alarm Systems/Description and
Operation/Immobilizer)
Electrical Information Reference
* Circuit Testing (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Circuit
Testing/Circuit Testing)
* Connector Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic
Procedures/Connector Repairs/Connector Repairs)
* Testing for Intermittent Conditions and Poor Connections (See: Testing and Inspection/Component Tests and General Diagnostics/General
Electrical Diagnostic Procedures/Circuit Testing/Testing for Intermittent Conditions and Poor Connections)
* Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Wiring
Repairs/Wiring Repairs)
Scan Tool Reference
Control Module References (See: Testing and Inspection/Programming and Relearning)for scan tool information
Circuit/System Verification
Note: Because of normal system communications between the BCM and ECM, any immobilizer B-codes must be diagnosed prior to the diagnosis
of P-codes.
Perform the ECM immobilizer learn using the Engine Control Module IMMO Learn function in SPS. Refer to Immobilizer System Component
Programming (See: Accessories and Optional Equipment/Antitheft and Alarm Systems/Testing and Inspection/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 K20 Engine Control Module.
Repair Instructions
Perform the Diagnostic Repair Verification (See: Verification Tests) after completing the diagnostic procedure.
Control Module References (See: Testing and Inspection/Programming and Relearning)for ECM replacement, setup, and programming
P0634
DTC P0634
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic System
Check - Vehicle) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Strategy Based Diagnosis) for an
overview of the diagnostic approach.
* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure
Instructions) provides an overview of each diagnostic category.
DTC Descriptor
DTC P0634
- Transmission Control Module (TCM) Overtemperature
Circuit/System Description
