Buick Regal: Memory Seat Feature Malfunction

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

1. Memory seat feature is inoperative

Circuit/System Description

Low reference is supplied to the seat memory switch from the seat memory control module. When a memory switch is pressed, the signal circuit from the seat memory control module is pulled low through the switch contacts and series of resistors indicating the memory recall request. In response to this signal, the seat memory control module commands the appropriate seat motors to move to the prerecorded seat positions stored in memory.

Diagnostic Aids

• The seat memory control module must be awake when measuring voltage from either one of the memory seat switch signal circuits. Voltage readings of 0.0 V or 5.0 V are possible if the module is not fully awake and result in misdiagnosing the circuit.
• When using remote keyless entry for vehicle access, the driver seat memory functions will operate only with transmitters 1 and 2. Transmitters 3 - 8 cannot be programmed for memory seat functions.

Reference Information

Schematic Reference

• Driver Seat Wiring Schematics
• Passenger Seat Wiring Schematics

Connector End View Reference

Component Connector End View Index

Description and Operation

Memory Seats Description and Operation

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

Scan Tool Reference

Control Module References for scan tool information.

Circuit/System Verification

1. Ignition ON.

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

• If any manual power seat function does not operate

Refer to Power Seat Malfunction (Driver or Passenger without Memory A44 or A45), Power Seat Malfunction (Driver Seat with Memory A45), or Power Seat Malfunction (Passenger Seat with Memory A44)

• Go to next step: If all manual power seat functions operate

3. Refer to Circuit/System Testing.

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the appropriate seat memory switch listed below:

• S47D Seat Memory Switch - Driver
• S47P Seat Memory Switch - Passenger

2. Test for less than 30 Ω between the low reference circuit terminal 1 and ground.

• If 30 Ω or greater

1. Ignition OFF, disconnect the X6 harness connector at the K40 Seat Memory Control Module.
2. Test for less than 2 Ω in the low reference circuit end to end
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K40 Seat Memory Control Module.

• Go to next step: If less than 30 Ω

3. Ignition ON, press a power seat switch in order to wake up the K40 Seat Memory Control Module.

4. Test for 9 V or greater between each signal circuit terminal listed below and ground:

• Memory set switch signal terminal 5
• Memory switch signal terminal 6
• If less than 9 V

1. Ignition OFF, disconnect the X6 harness connector at the K40 Seat Memory Control Module.
2. Test for infinite resistance between the signal circuit and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • Go to next step: If infinite resistance
3. Test for less than 2 Ω in the signal circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K40 Seat Memory Control Module.

• Go to next step: If 9 V or greater

5. Ignition OFF, disconnect the X6 harness connector at the K40 Seat Memory Control Module, ignition ON.

6. Test for less than 1 V between each signal circuit terminal listed below and ground:

• Memory set switch signal terminal 5
• Memory switch signal terminal 6
• If 1 V or greater

Repair the short to voltage on the circuit.

• Go to next step: If less than 1 V

7. Test or replace the S47 Seat Memory Switch.

Component Testing

Seat Memory Switch

1. Ignition OFF, disconnect the harness connector at the S47 Seat Memory Switch.

2. Test for infinite resistance between each signal terminal listed below and the low reference terminal 1 with the switch in the open position.

• Terminal 5
• Terminal 6
• If less than infinite resistance

Replace the S47 Seat Memory Switch.

• Go to next step: If infinite resistance

3. Test for less than 4 Ω between the signal terminal 5 and the low reference terminal 1 while pressing the memory SET button.

• If 4 Ω or greater

Replace the S47 Seat Memory Switch.

• Go to next step: If less than 4 Ω

4. Test for 573 - 701 Ω between the signal terminal 6 and the low reference terminal 1 while pressing the memory 1 button.

• If not between 573 - 701 Ω

Replace the S47 Seat Memory Switch.

• Go to next step: If between 573 - 701 Ω

5. Test for 1800 - 2201 Ω between the signal terminal 6 and the low reference terminal 1 while pressing the memory 2 button.

• If not between 1800 - 2201 Ω

Replace the S47 Seat Memory Switch.

• Go to next step: If between 1800 - 2201 Ω

6. Test for 5.52k - 6.73 kΩ between the signal terminal 6 and the low reference terminal 1 while pressing the Exit button.

• If not between 5.52k - 6.73 kΩ

Replace the S47 Seat Memory Switch.

• Go to next step: If between 5.52k - 6.73 kΩ

7. All OK.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

• Front Seat Adjuster Memory Switch Replacement
• Control Module References for K40D Seat Memory Control Module - Driver or K40P Seat Memory Control Module - Passenger replacement, programming and setup

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