FixVault

Circuit/System Testing

WARNING: This page is about a different car, the 2007 Saturn Outlook. However, it is still accessible from the selected car via links, so may be relevant.
  1. Clear the DTC.
  2. Use a scan tool to monitor the Dimming Control Reference Signal data parameter in the BCM data list.
    • If less than 0.33 volt, test the I/P dimming voltage reference circuit for a short to ground or an open/high resistance and test the stop lamp signal circuit for a short to ground. If the circuit/connections test normal, replace the BCM.
    • If greater than 4.97 volts, test the I/P dimming voltage reference circuit for a short to voltage. If the circuit/connections test normal, replace the BCM.
  3. If the voltage is correct and all circuits/connections test normal, replace the headlamp switch.