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Circuit/System Testing

WARNING: This page is about a different car, the 2010 Saturn Sky and 2010 Pontiac Solstice. However, it is still accessible from the selected car via links, so may be relevant.
  1. Ignition OFF, disconnect the harness connector at the CHMSL.
  2. Connect a test lamp between the signal circuit terminal A and ground.
  3. Ignition ON, command the CHMSL ON and OFF by applying and releasing the brake pedal. The test lamp should turn ON and OFF as the brake pedal is applied and released.
    • If the test lamp is always OFF, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the BCM.
    • If the test lamp is always ON, test the signal circuit for a short to voltage. If the circuit tests normal, replace the BCM.
  4. If all circuits test normal, replace the CHMSL.
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