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Circuit/System Testing

WARNING: This page is about a different car, the 2007 Cadillac SRX. However, it is still accessible from the selected car via links, so may be relevant.

I/P Dimming Voltage Reference Malfunction

  1. Ignition OFF, disconnect the harness connector at the I/P Dimmer switch.
  2. Ignition OFF, verify that a test lamp illuminates between B+ and the ground circuit terminal 10.
    • If the test lamp does not illuminate, test the ground circuit for an open/high resistance.
  3. Ignition ON, test for B+ between the I/P dimming voltage reference circuit terminal 5 and ground.
    • If less than the specified range, test the voltage reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the BCM.
    • If greater than the specified range, test the voltage reference circuit for a short to voltage. If the circuit tests normal, replace the BCM.
  4. If all circuits test normal, test or replace the I/P dimmer switch.

I/P Lamps Dimmer Switch Signal Malfunction

  1. Ignition OFF, disconnect the C2 harness connector at the BCM.
  2. Verify that a test lamp illuminates between the BCM 7 fuse voltage supply circuit terminal 2 and ground.
    • If the test lamp does not illuminate, test the voltage supply circuit for a short to ground or an open/high resistance.
  3. Reconnect the C2 harness connector at the BCM.
  4. Ignition ON, with a scan tool clear all DTCs.
  5. Ignition OFF, disconnect the harness connectors at the following components:
    • Hazard switch
    • Power window switch - LR
    • Power window switch - RR
    • PRNDL lamp
    • Front sunroof switch
    • Rear HVAC switch - front
    • Rear HVAC switch - rear
    • Rear sunroof sunshade switch
    • Rear wiper switch
    • Steering wheel controls
    • Tow/haul switch
    • Traction control switch
  6. Ignition ON, operate the vehicle within the conditions for running the DTC and verify the DTC does not reset.
    • If the DTC resets, test the I/P lamps dimmer switch signal circuit for a short to ground. If the circuits test normal, replace the BCM.
  7. Reconnect each component one at a time and verify that the DTC does not reset as current.
    • If the DTC resets as current, test or replace the component responsible for setting the DTC.
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