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Circuit/System Testing

WARNING: This page is about a different car, the 2008 Buick LaCrosse and 2008 Buick Allure. However, it is still accessible from the selected car via links, so may be relevant.
  1. Ignition OFF, disconnect the X-1 harness connector at the BCM.
  2. Verify that there is less than a 2 volt difference between the battery positive voltage circuit terminal 51 and the ground circuit terminal 19, and between the battery positive voltage circuit terminal 52 and the ground circuit terminal 17.
    • If greater than the specified range, test the voltage circuits for a short to ground or open/high resistance, and the ground circuits for open/high resistance.
  3. If the circuits test normal, replace the BCM.