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Memory Seat Feature Inoperative



Memory Seat Feature Inoperative

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (Initial Inspection and Diagnostic Overview) prior to using this diagnostic procedure.
* ReviewStrategy 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.


Diagnostic Fault Information





Circuit/System Description

Reference voltage is supplied to the memory switch from the driver door module (DDM). When a memory switch is pressed, reference voltage is applied through the switch contacts, a series of resistors and thorough the memory switch signal circuit to the DDM. The door module then sends a serial data message to the memory seat module (MSM) indicating the memory recall request. The MSM then commands the appropriate seat motors to move to the pre-recorded seat positions stored in memory in response to the switch input.

Diagnostic Aids

The DDM is referenced in Tech 2 as the Driver Door Switch.

Reference Information
Schematic Reference

Driver Seat Schematics (Driver Seat Schematics)
Connector End View Reference

Component Connector End Views (Connector Views)
Description and Operation

Memory Seats Description and Operation (Memory Seats Description and Operation)
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

1. Verify that all manual power seat and lumbar functions operate when being controlled by the seat and lumbar adjuster switches.

• If any seat function does not operate, Refer to Power Seat Inoperative (Without Memory A45) (Power Seat Inoperative (Without Memory A45))Power Seat Inoperative (With Memory A45) (Power Seat Inoperative (With Memory A45)) orLumbar Support Inoperative (Without Memory A45) (Lumbar Support Inoperative (Without Memory A45))Lumbar Support Inoperative (With Memory A45) (Lumbar Support Inoperative (With Memory A45)) .

2. Verify that the memory recall personalization option is ON. Refer to the owners manual.
3. Verify that memory positions for driver 1 and driver 2 have been recorded to memory by observing the scan tool Driver Position Module, Memory Data 1 and Memory Data 2 parameters.


Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the heated and cooled seat switch.
2. Ignition ON, verify that a test lamp illuminates between the reference voltage circuit terminal 1 and ground.

• If the test lamp does not illuminate, test the reference voltage circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the DMM.

3. Test for less than 1 volt between the signal circuit terminal 9 and ground.

• If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the DDM.

4. Ignition OFF, connect the harness connector at the heated/cooled seat switch.
5. Ignition ON, verify the scan tool Driver Door Switch Memory Recall Switches parameter is approximately 2.75 volts while pressing the memory 1 switch.

• If not the specified value, test the signal circuit terminal 9 for a short to ground or an open/high resistance. If the circuit tests normal, perform the Memory Switch component test. If the switch tests normal, replace the DDM.

6. Verify the scan tool Memory Recall Switches parameter is approximately 1.75 volts while pressing the memory 2 switch.

• If not the specified value, test or replace the heated/cooled seat switch.

7. Verify the scan tool Memory Recall Switches parameter is approximately 1.0 volt while pressing the EXIT switch.

• If not the specified value, test or replace the heated/cooled seat switch.

8. If all circuits test normal, replace the MSM.


Component Testing

Memory Switch
1. Disconnect the harness connector at the heated/cooled seat switch.
2. Test for infinite resistance between the signal circuit terminal 9 and the reference voltage circuit terminal 1 with the switch in the open position.

• If not the specified value, replace the heated/cooled seat switch.

3. Test the resistance between terminal 1 and terminal 9 while pressing the memory 1, memory 2, and EXIT buttons. Compare the resistance readings to the values in the Memory Switch Values table below.

• If the resistance is not within the specified range, replace the heated/cooled seat switch.






Repair Instructions

Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.

* Driver Seat Adjuster Memory Switch Replacement (Service and Repair)
* Control Module References (Programming and Relearning) for MSM and DDM replacement, setup, and programming

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