Diagnostic Test

WARNING: This page is about a different car, the 2017 Jeep Cherokee. However, it is still accessible from the selected car via links, so may be relevant.

CHECK FOR AN ACTIVE DIAGNOSTIC TROUBLE CODE (DTC)
1. Turn the ignition on.
2. Turn the Headlamps on.
3. With the scan tool, read the DTCs.
  Does the scan tool display this DTC as active?
  
  Yes
  - Go To 2
  No
  - Test complete. The condition or conditions that originally set this DTC are not present at this time. Using the wiring diagrams as a guide, check all related splices and connectors for signs of water intrusion, corrosion, pushed out or bent terminals and correct pin tension.
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
CHECK (L116) FOG LAMP SWITCH SIGNAL CIRCUIT FOR A SHORT TO VOLTAGE
1. Turn the ignition off.
2. Disconnect the Headlamp Switch harness connector.
3. Disconnect the BCM C8 harness connector.
4. Turn the ignition on.
5. Measure the voltage of the (L116) Fog Lamp Switch Signal circuit.
  Is there any voltage present?
  
  Yes
  - Repair the (L116) Fog Lamp Switch Signal circuit for a short to voltage.
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  No
  - Go To 3
CHECK THE (L116) FOG LAMP SWITCH SIGNAL CIRCUIT FOR AN OPEN IN THE HARNESS
1. Turn the ignition off.
2. Measure the resistance of the (L116) Fog Lamp Switch Signal circuit between the Headlamp harness connector and the BCM C8 harness connector.
  Is the resistance below 5.0 Ohms?
  
  Yes
  - Go To 4
  No
  - Repair the open in the (L116) Fog Lamp Switch Signal circuit.
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
CHECK THE HEADLAMP SWITCH
1. Connect the BCM C8 harness connector.
2. Connect a jumper wire between ground and the (L116) Fog Lamp Switch Signal circuit at the Headlamp Switch harness connector.
3. Turn the ignition on.
4. With the scan tool, read the DTCs.
  Does the scan tool display DTC: B2880-11-FOG LAMP CONTROL-CIRCUIT SHORT TO GROUND?
  
  Yes
  - Replace the Headlamp Switch in accordance with the Service Information. Refer to SWITCH, HEADLAMP, REMOVAL .
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  No
  - Replace the BCM in accordance with the Service Information. Refer to MODULE, BODY CONTROL (BCM), REMOVAL .
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .