Circuit/System Testing

2008 Chevrolet Chevy Express G3500, Van Passenger ExtendedSECTION Circuit/System Testing
WARNING: This page is about a different car, the 2009 Cadillac STS. However, it is still accessible from the selected car via links, so may be relevant.
  1. Ignition OFF, disconnect the harness connector at the lumbar switch.
  2. Test for less than 1 ohm between the ground circuit terminal E and ground.
    • If greater than the specified value, test the ground circuit for an open/high resistance.
  3. Ignition ON, verify that a test lamp illuminates between the B+ circuit terminal G and ground.
    • If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.
  4. Ignition OFF, connect the harness connector at the lumbar switch and disconnect the harness connector at the appropriate lumbar motor.
  5. Ignition ON, verify that the test lamp illuminates between control circuit terminal A and control circuit terminal B while pressing the lumbar switch in both directions.
    • If the test lamp does not illuminate for both directions, test the control circuits for a short to ground or an open/high resistance. If the circuits test normal, test or replace the lumbar switch.
  6. If all circuits test normal, test or replace the lumbar motor.
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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • β€’ You smell fuel, burning insulation, or see smoke.
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