Diagnostic Test

CHECK FOR AN ACTIVE DTC
1. With the scan tool, read Body Control Module (BCM) DTCs and record on the repair order.
2. Record the Environmental Data and any DTCs.
3. With the scan tool, erase DTCs.
4. Using the recorded Environmental Data, along with the When Monitored and Set Conditions above, operate the vehicle in the conditions that set the DTC.
5. With the scan tool, read BCM DTCs.
  Did the DTC return?
  
  Yes
  - Go To 2
  No
  - Perform the TESTING FOR AN INTERMITTENT CONDITION procedure. Refer to TESTING FOR AN INTERMITTENT CONDITION .
CHECK FOR ADDITIONAL BCM DTCS
1. With the scan tool, read BCM DTCs.
  Are there other Headlamp Switch related DTCs active in the BCM?
  
  Yes
  - Repair any other Headlamp Switch related DTCs before proceeding with this diagnostic procedure.
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  No
  - Go To 3
CHECK THE (D24) FRONT FOG LAMP RELAY CONTROL CIRCUIT FOR A SHORT TO VOLTAGE
1. Turn the ignition off.
2. Disconnect the Headlamp Switch harness connector.
3. Turn the ignition on.
4. Measure the voltage on the (D24) Front Fog Lamp Relay Control circuit at the Headlamp Switch harness connector.
  Is there any voltage present?
  
  Yes
  - Go To 5
  No
  - Go To 4
CHECK THE (D24) FRONT FOG LAMP RELAY CONTROL CIRCUIT FOR AN OPEN OR HIGH RESISTANCE
1. Turn the ignition off.
2. Disconnect the BCM C8/H harness connector.
3. Measure the resistance on the (D24) Front Fog Lamp Relay Control circuit between the Headlamp Switch harness connector and BCM C8/H harness connector - terminal 10.
  Is the resistance above 3.0 Ohms?
  
  Yes
  - Repair the open or high resistance on the (D24) Front Fog Lamp Relay Control circuit.
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  No
  - Replace the Headlamp Switch in accordance with the Service Information. Refer to SWITCH, HEADLAMP, REMOVAL AND INSTALLATION .
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
CHECK THE (D24) FRONT FOG LAMP RELAY CONTROL CIRCUIT FOR A SHORT TO ANOTHER CIRCUIT IN THE HARNESS CONNECTOR
1. Turn the ignition off.
2. Disconnect the BCM C8/H harness connector.
3. Check for continuity between the (D24) Front Fog Lamp Relay Control circuit and all other circuits on the Headlamp Switch harness connector.
4. Check for continuity between the (D24) Front Fog Lamp Relay Control circuit and all other circuits on the BCM C8/H harness connector.
  Is there continuity between the (D24) Front Fog Lamp Relay Control circuit and any other circuit(s)?
  
  Yes
  - Repair the short between the (D24) Front Fog Lamp Relay Control circuit and the circuit that has continuity.
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  No
  - Replace the Headlamp Switch in accordance with the Service Information. Refer to SWITCH, HEADLAMP, REMOVAL AND INSTALLATION .
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .