LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Cadillac >> 2007 >> Escalade EXT >> Repair and Diagnosis >> External Pages >> Different car >> Section 1075 (Power Seat System) >> Diagnostic Information and Procedures >> Power Seat Inoperative (w/Memory) >> Circuit/System Testing
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Circuit/System Testing

WARNING: This page is about a different car, the 2008 GMC Sierra, 2008 GMC Cab & Chassis Sierra, 2008 Chevrolet Silverado, and 2008 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.

Power Seat Switch Circuit Test

  1. Ignition OFF, disconnect the harness connector at the power seat switch.
  2. Ignition ON, verify that a test lamp illuminates between the B+ reference circuit terminal E and ground.
    • If the test lamp does not illuminate, test the B+ reference circuit for a short to ground or an open/high resistance.
  3. Verify the scan tool power seat switch parameters are Inactive.
    • If not the specified values, test the affected signal circuit terminal listed for a short to voltage. If the circuit tests normal, replace the MSM.
      • Front vertical down switch terminal K
      • Front vertical up switch terminal A
      • Horizontal forward switch terminal D
      • Horizontal rearward switch terminal C
      • Rear vertical down switch terminal J
      • Rear vertical up switch terminal F
      • Recline forward switch terminal H
      • Recline rearward switch terminal G
  4. Install a 3A fused jumper wire between the affected signal circuit terminal listed and the B+ reference circuit terminal E. Verify the affected scan tool power seat switch parameter is Acitve.
    • Front vertical down switch terminal K
    • Front vertical up switch terminal A
    • Horizontal forward switch terminal D
    • Horizontal rearward switch terminal C
    • Rear vertical down switch terminal J
    • Rear vertical up switch terminal F
    • Recline forward switch terminal H
    • Recline rearward switch terminal G
    • If not the specified value, test the signal circuit for an open/high resistance. If the circuit tests normal, replace the MSM.
  5. If all circuits test normal, test or replace the power seat switch.

Lumbar Switch Circuit Test

  1. Ignition OFF, disconnect the harness connector at the lumbar switch.
  2. Ignition ON, verify that a test lamp illuminates between the B+ reference circuit terminal G and ground.
    • If the test lamp does not illuminate, test the B+ reference circuit for a short to ground or an open/high resistance.
  3. Verify the scan tool lumbar switch parameters are Inactive.
    • If not the specified values, test the affected signal circuit terminal listed for a short to voltage. If the circuit tests normal, replace the MSM.
      • Lumbar down switch terminal K
      • Lumbar up switch terminal A
      • Lumbar forward switch terminal D
      • Lumbar rearward switch terminal C
  4. Install a 3A fused jumper wire between the affected signal circuit terminal listed and the B+ reference circuit terminal G. Verify the affected scan tool lumbar switch parameter is Acitve.
    • Lumbar down switch terminal K
    • Lumbar up switch terminal A
    • Lumbar forward switch terminal D
    • Lumbar rearward switch terminal C
    • If not the specified value, test the signal circuit for an open/high resistance. If the circuit tests normal, replace the MSM.
  5. If all circuits test normal, test or replace the lumbar switch.

Seat Adjuster Motor Control Circuit Test

  1. Ignition OFF, disconnect the X1 harness connector at the seat adjuster assembly.
  2. Ignition OFF, test for less than 1.0 ohm between the affected control circuit terminal listed and ground.
    • Rear vertical terminal 1
    • Front vertical terminal 2
    • Horizontal terminal 3
    • If greater than the specified range, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the MSM.
  3. Ignition OFF, test for less than 1.0 ohm between the affected control circuit terminal listed and ground.
    • Rear vertical terminal 4
    • Front vertical terminal 5
    • Horizontal terminal 6
    • If greater than the specified range, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the MSM.
  4. Connect a test lamp between the affected control circuit terminals listed.
    • Rear vertical terminal 1 to terminal 4
    • Front vertical terminal 2 to terminal 5
    • Horizontal terminal 3 to terminal 6
  5. Command the affected function in both directions with a scan tool. The test lamp should turn ON when commanding the affected function in both states.
    • If the test lamp remains OFF during either of the commands, test for a short to ground on either control circuit. If the circuits test normal, replace the MSM.
  6. If all circuits test normal, test or replace the seat adjuster.

Recline Motor Control Circuit Test

  1. Ignition OFF, disconnect the harness connector at the recline motor.
  2. Ignition OFF, test for less than 1.0 ohm between the control circuit terminal A and ground.
    • If greater than the specified range, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the MSM.
  3. Ignition OFF, test for less than 1.0 ohm between the control circuit terminal B and ground.
    • If greater than the specified range, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the MSM.
  4. Connect a test lamp between control circuit terminal A and control circuit terminal B.
  5. Command the recline Forward and Rearward with a scan tool. The test lamp should turn ON when commanding the Forward and Rearward states.
    • If the test lamp remains OFF during either of the commands, test for a short to ground on either control circuit. If the circuits test normal, replace the MSM.
  6. If all circuits test normal, test or replace the recliner motor.

Lumbar Motor Control Circuit Test

  1. Ignition OFF, disconnect the X1 harness connector at the lumbar adjuster assembly.
  2. Ignition OFF, test for less than 1.0 ohm between the affected control circuit terminal listed and ground.
    • Vertical lumbar terminal A
    • Horizontal lumbar terminal C
    • If greater than the specified range, test the control circuit for a short to voltage or an open/high resistance. If circuit tests normal, replace the MSM.
  3. Ignition OFF, test for less than 1.0 ohm between the affected control circuit terminal listed and ground.
    • Vertical lumbar terminal B
    • Horizontal lumbar terminal D
    • If greater than the specified range, test the control circuit for a short to voltage or an open/high resistance. If circuit tests normal, replace the MSM.
  4. Connect a test lamp between affected control circuit terminals listed.
    • Vertical lumbar terminal A to terminal B
    • Horizontal lumbarterminal C to terminal D
  5. Command the affected function in both directions with a scan tool. The test lamp should turn ON when commanding the affected function in both states.
    • If the test lamp remains OFF during either of the commands, test for a short to ground on either control circuit. If the circuits test normal, replace the MSM.
  6. If all circuits test normal, test or replace the lumbar support.
scientia non olet · About LEMON Manuals