9-7X V8-5.3L (2005)
Control Module References (See: Testing and Inspection/Programming and Relearning/Control Module References) for scan tool information
Circuit/System Verification
1. Ignition ON, observe the scan tool DDM, PDM Heated Seat Switch and Back Only Heat Switch parameters while pressing and releasing each of
the switches. The readings should change between Active and Inactive.
‹› If not the specified value, replace the affected door module.
2. Observe the scan tool MSM Seat Heat Zone and Seat Temp. Setting parameters while operating the heated seat in all operating modes. The
readings should change in relation to the heated seat switch operation.
‹› If not the specified value, replace the MSM.
3. If the heated seat switch inputs test normal, refer to Heated Seat Control Circuit Test.
Circuit/System Testing
1. Disconnect the harness connector at the affected seat heater element.
2. Connect a test lamp between the control circuit terminal A and the control circuit terminal B.
3. Command the heated seat ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states.
‹› If the test lamp is always ON, test the control circuit terminal A for a short to voltage. If the circuit tests normal, replace the MSM.
‹› If the test lamp is always OFF, test the control circuit terminals A and B for a short to ground or an open/high resistance. If the circuit tests
normal, replace the MSM.
4. If all circuits test normal, test or replace the affected seat heater element.
Repair Instructions
Perform the Diagnostic Repair Verification (See: Powertrain Management/Computers and Control Systems/Testing and Inspection/Diagnostic Trouble
Code Tests and Associated Procedures/Verification Tests and Procedures) after completing the diagnostic procedure.
Control Module References (See: Testing and Inspection/Programming and Relearning/Control Module References) for MSM or DDM replacement,
programming, and setup.
Symptoms - Seat Heating and Cooling
Symptoms - Seat Heating and Cooling
Important: The following steps must be completed before using the symptom tables.
1. Perform the Diagnostic System Check - Vehicle (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic System
Check - Vehicle) before using the Symptom Tables in order to verify that all of the following are true:
*
There are no DTCs set.
*
The control modules can communicate via the serial data link.
2. Review the system operation in order to familiarize yourself with the system functions. Refer to Heated Seats Description and Operation (See:
Description and Operation).
Visual/Physical Inspection
*
Inspect for aftermarket devices which could affect the operation of the system. Refer to Checking Aftermarket Accessories (See: Testing and
Inspection/Component Tests and General Diagnostics/Checking Aftermarket Accessories).
*
Inspect the easily accessible or visible system components for obvious damage or conditions which could cause the symptom.
Intermittent
Faulty electrical connections or wiring may be the cause of intermittent conditions. Refer to Testing for Intermittent Conditions and Poor Connections (
See: Testing and Inspection/Component Tests and General Diagnostics/Circuit Testing/Testing for Intermittent Conditions and Poor Connections).
Symptom List
