Diagnostic Test

WARNING: This page is about a different car, the 2020 Jeep Cherokee. However, it is still accessible from the selected car via links, so may be relevant.

CHECK FOR AN ACTIVE DTC
1. Turn the ignition on.
2. With the scan tool, read 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 FOR AN ACTIVE DTC WITH THE LEFT HEADLAMP ASSEMBLY DISCONNECTED
1. Turn the ignition off.
2. Disconnect the Left Headlamp Assembly C2 harness connector.
3. Turn the ignition on.
4. Wait 10 seconds.
5. With the scan tool, read DTCs.
  Does the scan tool display this DTC as active?
  
  Yes
  - Repeat this step for the Right Headlamp Assembly. If both headlamps assemblies are disconnected and the DTC is still active, Go To 3
  No
  - Replace the headlamp assembly, that when disconnected allowed the DTC to go to stored, in accordance with the Service Information. Refer to UNIT, FRONT LAMP, REMOVAL .
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
CHECK THE (D503) LIN BUS CIRCUIT FOR A SHORT TO VOLTAGE
1. Turn the ignition off.
2. Disconnect the AFLS harness connector.
3. Disconnect Both Headlamp Assembly connectors.
4. Turn the ignition on.
5. Measure the voltage between ground and the (D503) LIN Bus circuit.
  Is there any voltage present?
  
  Yes
  - Repair the short to voltage on the (D503) LIN Bus circuit.
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  No
  - Go To 4
CHECK THE (D503) LIN BUS CIRCUIT FOR A SHORT TO GROUND
1. Measure the resistance between ground and the (D503) LIN Bus circuit.
  Is the resistance below 10k Ohms?
  
  Yes
  - Repair the short to ground in the (D503) LIN Bus circuit.
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  No
  - Go To 5
CHECK THE (D503) LIN BUS CIRCUIT FOR AN OPEN
1. Turn the ignition off.
2. Measure the resistance of the (D503) LIN Bus circuit between the Left and Right Headlamp Assembly C2 harness connectors.
  Is the resistance above 5 Ohms?
  
  Yes
  - Repair the open in the (D503) LIN Bus circuit.
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  No
  - Replace the AFLS in accordance with the Service Information. Refer to MODULE, ADAPTIVE FRONT LIGHTING SYSTEM (AFLS), REMOVAL .
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .