Diagnostic Instructions
| • | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
| • | 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 | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
|---|---|---|---|---|
Heated and Cooled Seat Switch Ground | -- | 2 | -- | -- |
Heated Seat Back Only Mode Indicator Control | 4 | 4 | 4 | -- |
Heated Seat Back Only Mode Switch Signal | 3 | 3 | -- | -- |
Heated Seat Cool Indicator Control | 4 | 4 | 4 | -- |
Heated Seat Cool Switch Signal | 2 | 2 | -- | -- |
Heated Seat Heat Indicator Control | 4 | 4 | 4 | -- |
Heated Seat High Temperature Indicator Control | 4 | 4 | 4 | -- |
Heated Seat Low Temperature Indicator Control | 4 | 4 | 4 | -- |
Heated Seat Medium Temperature Indicator Control | 4 | 4 | 4 | -- |
Memory Switch Signal | 1 | 1 | -- | -- |
Memory Switch Supply Voltage | 5 | 1 | -- | -- |
Heated Seat Temperature Switch Signal | 2 | 2 | -- | -- |
1. Memory Seat Feature Inoperative 2. Heated/Cooled Seats Inoperative 3. Heated/Cooled Seat Inoperative - Back Only Mode 4. Heated/Cooled Seat Switch Indicator Malfunction | ||||
Circuit/System Description
Battery positive voltage is supplied to the memory function 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 control 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. |
| • | The MSM is referenced in the Tech 2 as the Driver Position Module. |
Reference Information
Schematic Reference
Connector End View Reference
Power Seat Connector End Views
Electrical Information Reference
Scan Tool Reference
Circuit/System Verification
- Verify that all manual power seat and lumbar functions operate as described in the description and operation. Refer to Memory Seats Description and Operation .
- Verify that the memory recall personalization option is ON. Refer to Personalization Description and Operation and Vehicle Personalization .
- 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
- Ignition ON, verify the scan tool Driver Door Switch Memory Recall Switches parameter changes state while pressing the memory 1 switch.
- Verify the scan tool Memory Recall Switches parameter changes state while pressing the memory 2 switch.
- Verify the scan tool Memory Recall Switches parameter changes state while pressing the EXIT switch.
- If all circuits test normal, replace the memory seat module.
| ⇒ | If the parameter does not change state, perform the Memory Switch component test. If the switch tests normal, replace the driver door module. |
| ⇒ | If the parameter does not change state, replace the memory switch. |
| ⇒ | If the parameter does not change state, replace the memory switch. |
Component Testing
Memory Function Switch
- Disconnect the (C4) harness connector at driver door module.
- Test for infinite resistance between the memory switch signal circuit terminal 5 and the switch supply voltage circuit terminal 14.
- Test the resistance between terminals 14 and 5. Press the memory 1, memory 2, and EXIT buttons and compare the resistance readings to the values in the Memory Switch Values table below.
| ⇒ | If not infinite, replace the memory switch. |
| ⇒ | If the resistance is not within the specified range, replace the memory switch. |
Switch Position | Resistance |
|---|---|
Idle | Infinite |
Memory 1 | 2.03K-2.49K ohms |
Memory 2 | 3.83K-4.69K ohms |
EXIT | 8.32K-10.18K ohms |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| • | Control Module References for MSM and DDM replacement, setup, and programming |
