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Circuit/System Testing

WARNING: This page is about a different car, the 2008 Cadillac STS. However, it is still accessible from the selected car via links, so may be relevant.
  1. Ignition ON, verify with a scan tool the Mirror Direction Switch parameter changes as the switch is activated. The scan tool should change between UP, DOWN, LEFT, RIGHT.
    • If the function does not perform as specified, replace the DDSA.
  2. Verify with a scan tool the mirror select switch parameter changes as the switch is activated. The scan tool should change between DRIVER and PASSENGER.
    • If the function does not perform as specified, replace the DDSA.
  3. Ignition OFF, disconnect the appropriate outside rearview mirror X1 harness connector.
  4. Ignition OFF, test for less than 1.0 ohm of resistance at each mirror motor control circuit between the outside rearview mirror X1 harness connector and ground.
    • If greater than the specified range, test the appropriate mirror motor control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the appropriate door control module.
  5. Connect a test lamp between mirror motor UP control circuit terminal A and mirror motor DOWN control circuit terminal C.
  6. Command the appropriate mirror to the UP and DOWN positions with a scan tool. The test lamp should turn ON when commanding the UP and DOWN states.
    • If the test lamp remains OFF during either of the commands, test for a short to ground on either control circuit. If the circuit tests normal, replace the appropriate door control module.
  7. Connect a test lamp between mirror motor LEFT control circuit terminal H and mirror motor RIGHT control circuit terminal F.
  8. Command the appropriate mirror to the LEFT and RIGHT positions with a scan tool. The test lamp should turn ON when commanding the LEFT and RIGHT states.
    • If the test lamp remains OFF during either of the commands, test for a short to ground on either control circuit. If the circuit tests normal, replace the appropriate door control module.
  9. If all circuits test normal, test or replace the appropriate outside rearview mirror.
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