Memory Seat Feature Inoperative

Memory Seat Feature Inoperative

Diagnostic Instructions

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

Diagnostic Fault Information






Circuit/System Description

Battery positive voltage is supplied to the memory switch from the driver door module (DDM). When a memory switch is pressed, battery 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 message via the GMLAN serial data line 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.

Circuit/System Verification

1. Verify that all manual power seat and lumbar functions operate as described in the description and operation. Refer to Memory Seats Description and Operation.
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 memory seat switch.
2. Ignition ON, test for B+ between the memory seat switch supply voltage circuit terminal 2 and ground.

^ If less than B+, test the supply voltage circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the DDM.

3. Test for 0 volts between the memory switch signal circuit terminal 1 and ground.

^ If greater than 0 volts, test the signal circuit for a short to voltage.

4. Ignition OFF, connect the harness connector at the memory seat switch.
5. Ignition ON, with a scan tool verify the Memory Recall Switch parameter changes state while pressing the memory 1, memory 2 and exit switches.

^ If the parameter does not change state while pressing each switch, test the memory switch signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, test or replace the memory seat switch.

6. If all circuits test normal, replace the DDM.

Component Testing

Memory Switch
1. Disconnect the harness connector at the memory seat switch.
2. Test for infinite resistance between the memory switch signal circuit terminal 1 and the switch supply voltage circuit terminal 2.

^ If not infinite, replace the memory seat switch.

3. Test the resistance between terminal 1 and terminal 2 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 memory seat switch.






Repair Instructions

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

* Driver Seat Adjuster Memory Switch Replacement