Diagnostic Test

WARNING: This page is about a different car, the 2015 Jeep Grand 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 .
(D412) LIN BUS CIRCUIT SHORTED TO VOLTAGE
1. Turn the ignition off.
2. Disconnect the Right Front Headlamp Assembly C1 harness connector.
3. Disconnect the Left Front Headlamp Assembly C1 harness connector.
4. Turn the ignition on.
5. Measure the voltage of the (D412) LIN Bus circuit.
  Is there any voltage present?
  
  Yes
  - Repair the (D412) LIN Bus circuit for a short to voltage.
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  No
  - Go To 3
(D412) LIN BUS CIRCUIT SHORTED TO GROUND
1. Turn the ignition off.
2. Measure the resistance between ground and the (D412) LIN Bus circuit.
  Is the resistance above 10K Ohms?
  
  Yes
  - Go To 4
  No
  - Repair the (D412) LIN Bus circuit for a short to ground.
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
(D412) LIN BUS CIRCUIT OPEN OR HIGH RESISTANCE
1. Measure the resistance of the (D412) LIN Bus circuit.
  Is the resistance below 5.0 Ohms?
  
  Yes
  - Replace the Adaptive Front Lighting System (AFLS) Module in accordance with the Service Information. Refer to UNIT, FRONT LAMP, REMOVAL .
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  No
  - Repair the (D412) LIN Bus circuit for an open or high resistance.
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .