Diagnostic Test

WARNING: This page is about a different car, the 2012 Jeep Liberty. However, it is still accessible from the selected car via links, so may be relevant.

VERIFY DTC IS ACTIVE
1. Turn the ignition on.
2. With the scan tool, read active Door Module DTCs.
  Does the scan tool display: U0037-LIN BUS CIRCUIT LOW as Active?
  
  Yes
  - Go To 2.
  No
  - Refer to COMMUNICATION - DIAGNOSIS AND TESTING and perform the Stored Lost Communication DTCs diagnostic procedure.
CHECK THE LIN BUS CIRCUIT

Fig 1: Checking LIN Bus Circuit
Courtesy of CHRYSLER GROUP, LLC
1. Turn the ignition off.
2. Disconnect the Driver Window/Door Lock Switch C2 connector.
3. Turn the ignition on.
4. Measure the voltage between the (D500) LIN Bus circuit and the (D501) Lin Bus Return circuit.
  Is the voltage above 7.0 volts?
  
  No
  - Go To 3.
  Yes
  - Replace the Driver Window/Door Lock Switch.
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
(D500) LIN BUS CIRCUIT SHORTED TO GROUND

Fig 2: Checking Driver Door Lin Bus Circuit For A Short To Ground
Courtesy of CHRYSLER GROUP, LLC
1. Turn the ignition off.
2. Disconnect the Driver Door Module C5 connector.
3. Measure the resistance between Ground and the (D500) LIN Bus circuit in the Door Module C5 connector.
  Is the resistance below 10, 000 Ohms?
  
  Yes
  - Repair the (D500) LIN Bus circuit for a short to the ground.
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  No
  - Go To 4.
(D500) LIN BUS CIRCUIT SHORTED TO THE (D501) LIN BUS RETURN CIRCUIT

Fig 3: Checking LIN BUS Circuit For A Short To The LIN BUS Return Circuit
Courtesy of CHRYSLER GROUP, LLC
1. Measure the resistance between the (D500) LIN Bus circuit and the (D501) LIN Bus Return circuit in the Door Module C5 connector.
  Is the resistance below 10, 000 Ohms?
  
  Yes
  - Repair the (D500) LIN Bus circuit for a short to the (D501) LIN Bus Sense Return circuit.
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  No
  - Replace the Driver Door Module in accordance with the Service Information.
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .