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.

TEST FOR INTERMITTENT CONDITION
NOTE:
Check for any TSB(s) related to the condition. If a TSB applies, perform the procedure outlined in the TSB before continuing.
1. Turn the ignition on.
  NOTE:
  Make sure the battery voltage is between 10.0 and 16.0 volts.
2. With the scan tool, read the module status.
  NOTE:
  Check the BCM for any active CAN hardware DTCs, perform DTC before proceeding.
  
  Does the scan tool indicate that the module is active on the bus?
  
  Yes
  - The no response condition is not present at this time. Using the wiring diagram/schematic as a guide, inspect the wiring for chafed, pierced, pinched, and partially broken wires and the wiring harness connectors for broken, bent, pushed out, and corroded terminals.
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  No
  - Go To 2
CHECK THE (A938) FUSED B(+) CIRCUIT FOR AN OPEN
1. Turn the ignition off.
2. Disconnect the Instrument Cluster harness connector.
3. Using a 12-volt test light connected to ground, check the (A938) Fused B(+) circuit.
  Does the test light illuminate brightly?
  
  Yes
  - Go To 3
  No
  - Repair the (A938) Fused B(+) circuit for an open or high resistance.
    NOTE:
    If the fuse is open, make sure to check for a short to ground.
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
CHECK THE (Z917) GROUND CIRCUIT FOR AN OPEN
1. Using a 12-volt test light connected to 12-volts, check each (Z917) Ground circuit.
  Does the test light illuminate brightly for each circuit?
  
  Yes
  - Go To 4
  No
  - Repair the (Z917) Ground circuit for an open or high resistance.
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
CHECK THE (F949) FUSED IGNITION CIRCUIT FOR AN OPEN OR SHORT
1. Turn the ignition on.
2. Using a 12-volt test light connected to ground, check the (F949) Fused Ignition circuit.
  Does the test light illuminate brightly?
  
  Yes
  - Go To 5
  No
  - Repair the (F949) Fused Ignition circuit for an open or high resistance.
    NOTE:
    If the fuse is open, make sure to check for a short to ground.
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
CHECK THE (D81) AND (D82) CAN C BUS CIRCUITS FOR AN OPEN
1. Turn the ignition off.
2. Disconnect the CAN C IP C4 Star Connector.
3. Measure the resistance of the (D82) CAN C Bus (-) circuit between the CAN C IP C4 Star Connector and the Instrument Cluster harness connector.
4. Measure the resistance of the (D81) CAN C Bus (+) circuit between the CAN C IP C4 Star Connector and the Instrument Cluster harness connector.
  Are both resistances below 5.0 Ohms?
  
  Yes
  - Replace the Instrument Cluster in accordance with the Service Information. Refer to REMOVAL .
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  No
  - Repair the (D81) or (D82) CAN C Bus circuit(s) for an open or high resistance.
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .