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Circuit/System Testing

WARNING: This page is about a different car, the 2007 Cadillac XLR. However, it is still accessible from the selected car via links, so may be relevant.
  1. Ignition OFF, disconnect the harness connector at the brake pedal position sensor.
  2. Ignition OFF, test for less than 1 ohm of resistance between the low reference circuit terminal A and ground.
    • If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the BCM.
  3. Ignition ON, test for 4.8-5.2 volts between the 5-volt reference circuit terminal C and ground.
    • If less than the specified range, test the 5-volt 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 5-volt 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 brake pedal position sensor.