Circuit/System Verification

Ignition ON.
Verify ALL turn signals operate when activated with the turn signal switch.
- If the turn signals do not operate when activated
  Refer to Turn Signal Lamps and/or Indicators Malfunction .
- Go to next step: If the turn signals operate when activated
Verify the scan tool Headlamps On Switch parameter changes between Active and Inactive while commanding the headlamps ON and OFF with the headlamp switch.
- If the parameter does not change
  Refer to Headlamp Switch Malfunction .
- Go to next step: If the parameter changes
Verify the scan tool Automatic Headlamps Disable Switch parameter changes between Active and Inactive while commanding the automatic lamp control ON and OFF with the headlamp switch.
- If the parameter does not change
  Refer to Headlamp Switch Malfunction .
- Go to next step: If the parameter changes
Verify the scan tool Headlamps Flash Switch parameter changes between Active and Inactive while commanding the flash to pass ON and OFF with the turn signal/multifunction switch.
- If the parameter does not change
  Refer to Turn Signal/Multifunction Switch Malfunction .
- Go to next step: If the parameter changes
Verify the scan tool High Beam Select Switch parameter changes between Active and Inactive while commanding the high beams ON and OFF with the turn signal/multifunction switch.
- If the parameter does not change
  Refer to Turn Signal/Multifunction Switch Malfunction .
- Go to next step: If the parameter changes
Verify the left low beam headlamp turns ON and OFF when commanding the Left Low Beam/Daytime Running Lamp ON and OFF with a scan tool.
- If the left low beam headlamp does not turn ON and OFF
  Refer to Headlamps Malfunction - Low Beam.
- Go to next step: If the left low beam headlamp turns ON and OFF
Verify the right low beam headlamp turns ON and OFF when commanding the Right Low Beam/Daytime Running Lamp ON and OFF with a scan tool.
- If the right low beam headlamp does not turn ON and OFF
  Refer to Headlamps Malfunction - Low Beam.
- Go to next step: If the right low beam headlamp turns ON and OFF
Verify the high beams turn ON and OFF when commanding the High Beams ON and OFF with a scan tool.
- If the high beams do not turn ON and OFF
  Refer to Headlamps Malfunction - High Beam .
- Go to next step: If the high beams turn ON and OFF
Verify the high beam indicator on the instrument cluster turns ON and OFF while commanding the All Indicators Test ON and OFF with a scan tool.
- If the high beam indicator does not turn ON and OFF
  Refer to High Beam Indicator Malfunction .
- Go to next step: If the high beam indicator turns ON and OFF
Verify the scan tool Ambient Light Status parameter changes while switching from dim to bright ambient light conditions
NOTE:
- Vehicles equipped with RPO CE1 use the B200 Rain Sensor Module for ambient light status. Vehicles without RPO CE1 use the B10B Ambient Light/Sunload Sensor for ambient light status.
- Placing a towel over the ambient light sensor can simulate a dim light condition and shining an incandescent light at the ambient light sensor can simulate a bright light condition.
- If the parameter does not change and the vehicle is equipped with RPO CE1
  Refer to Rain Sensing Module Malfunction .
- If the parameter does not change and the vehicle is not equipped with RPO CE1
  Refer to Ambient Light Sensor Malfunction .
- Go to next step: If the parameter changes
All OK.