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Circuit/System Testing

WARNING: This page is about a different car, the 2012 Chevrolet Malibu. However, it is still accessible from the selected car via links, so may be relevant.
  1. Ignition OFF, disconnect the harness connector at the ambient light sensor.
  2. Ignition OFF, exterior lamps OFF, key removed, wait 30 seconds, test for less than 10 ohms between the appropriate low reference circuit terminal listed below and ground.
    • Ambient light sensor low reference circuit terminal B - with C60
    • Ambient light sensor low reference circuit terminal C - with C68
    • If greater than the specified range, test the low reference circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the BCM.
  3. Ignition ON, verify the scan tool Ambient Light Sensor parameter is greater than 4.65 volts.
    • If less than the specified range, test the appropriate signal circuit terminal listed below for a short to ground. If the circuit tests normal, replace the BCM.
    • Ambient light sensor signal circuit terminal A - with C60
    • Ambient light sensor signal circuit terminal D - with C68
  4. Install a 3 A fused jumper wire between the appropriate signal and low reference circuit terminals listed below. Verify the scan tool Ambient Light Sensor parameter is less than 0.196 volts.
    • Ambient light sensor signal circuit terminal A and low reference circuit terminal B - with C60
    • Ambient light sensor signal circuit terminal D and low reference circuit terminal C - with C68
    • If greater than the specified range, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the BCM.
  5. If all circuits test normal, replace the ambient light sensor.
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