GM Service Manual Online
For 1990-2009 cars only

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

Memory Set Switch Signal

1

1

--

--

Memory Switch Signal

1

1

1

--

Memory Seat Adjuster Switch Low Reference

--

1

--

--

1. Memory seat feature inoperative

Circuit/System Description

Low reference is supplied to the memory seat adjuster switch from the memory seat module. When a memory switch is pressed, a low reference is applied through the switch contacts, a series of resistors and thorough the memory switch signal circuit to the memory seat module indicating the memory recall request. The memory seat module then commands the appropriate seat motors to move to the pre-recorded seat positions stored in memory in response to the switch input.

Reference Information

Schematic Reference

Driver Seat Schematics

Connector End View Reference

Component Connector End Views

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. Verify that all manual power seat functions operate when being controlled by the seat adjuster switches.
  2. If any seat function does not operate, refer to Power Seat Malfunction.
  3. Verify that the memory recall personalization option is ON. Refer to the owners manual.
  4. Verify that memory positions for driver 1, driver 2, and driver 3 have been recorded to memory by observing the scan tool Memory Seat Module, Memory Data 1, Memory Data 2, and Memory Data 3 parameters.

Circuit/System Testing

  1. Ignition OFF, disconnect the harness connector at the S47 memory seat adjuster switch.
  2. Test for less than 5 Ω between the low reference circuit terminal 5 and ground.
  3. If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the K40 memory seat module.
  4. Ignition ON, test for 4.8 -5.2 V between the signal circuit terminal 6 and ground.
  5. If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the K40 memory seat module.
    If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K40 memory seat module.
  6. Ignition ON, test for 4.8 -5.2 V between the signal circuit terminal 1 and ground.
  7. If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the K40 memory seat module.
    If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K40 memory seat module.
  8. If all circuits test normal, test or replace the S47D memory seat adjuster switch.

Component Testing

Memory Seat Adjuster Switch

  1. Disconnect the harness connector at the S47D memory seat adjuster 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.
  3. If not the specified value, replace the heated/cooled seat switch.
  4. Test the resistance between terminal 5 and terminal 6 while pressing the memory 1, memory 2, and memory 3 buttons. Compare the resistance readings to the values in the Memory Switch Values table below.
  5. If the resistance is not within the specified range, replace the S47D memory seat adjuster switch.
  6. Test for less than 1 Ω between terminal 5 and terminal 1 while pressing the memory set switch.
  7. If greater than the specified range, replace the S47D memory seat adjuster switch.

Memory Switch Values

Switch Position

Resistance

Idle

Infinite

Memory 1

2.03K-2.49K Ω

Memory 2

3.83K-4.69K Ω

Memory 3

8.33K-10.18K Ω

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for K40 memory seat module replacement, setup, and programming