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 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 THE ABILITY OF THE BCM AND PCM TO READ THE FUEL LEVEL SENSOR SIGNAL
1. Turn the ignition off.
2. Disconnect the Fuel Pump Module harness connector.
3. Turn the ignition on.
4. With the scan tool, read BCM and PCM DTCs.
  NOTE:
  The scan tool should display the P0460-15-FUEL LEVEL SENSOR 1 - CIRCUIT SHORT TO BATTERY OR OPEN in the BCM or P0463-FUEL LEVEL SENSOR CIRCUIT HIGH DTC in the PCM as active or pending with the connector unplugged.
  
  Does the scan tool display as described above?
  
  Yes
  - Verify that there is good pin to terminal contact in the Fuel Level Sensor harness connector. If no problems are found, replace the Fuel Level Sensor. GAS: Refer to MODULE, FUEL PUMP, REMOVAL .
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  No
  - Go To 3
CHECK THE (N4) FUEL LEVEL SENSOR SIGNAL CIRCUIT FOR A SHORT TO GROUND
1. Turn the ignition off.
2. Disconnect the BCM harness connector.
3. Check for continuity between ground and the (N4) Fuel Level Sensor Signal circuit at the Fuel Level Sensor harness connector.
  Is there continuity between ground and the (N4) Fuel Level Sensor Signal circuit?
  
  Yes
  - Repair the (N4) Fuel Level Sensor Signal circuit for a short to ground.
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  No
  - Go To 4
CHECK FOR THE (N4) FUEL LEVEL SENSOR SIGNAL CIRCUIT SHORTED TO THE (G109) FUEL LEVEL SENSE RETURN CIRCUIT
1. Check for continuity between the (N4) Fuel Level Sensor Signal circuit and the (G109) Fuel Level Sense Return circuit at the Fuel Level Sensor harness connector.
  Is there continuity between the (N4) Fuel Level Sensor Signal circuit and the (G109) Fuel Level Sense Return circuit?
  
  Yes
  - Repair the short between the (N4) Fuel Level Sensor Signal circuit and the (G109) Fuel Level Sense Return circuit.
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  No
  - Go To 5
CHECK RELATED BCM HARNESS CONNECTIONS
1. Perform any Service Bulletins that apply.
2. Disconnect all BCM harness connectors.
3. Disconnect all related in-line harness connections (if equipped).
4. Disconnect the related component harness connectors.
5. Inspect harness connectors, component connectors, and all male and female terminals for the following conditions:
  - Proper connector installation.
  - Damaged connector locks.
  - Corrosion.
  - Other signs of water intrusion.
  - Weather seal damage (if equipped).
  - Bent terminals.
  - Overheating due to a poor connection (terminal may be discolored due to excessive current draw).
  - Terminals that have been pushed back into the connector cavity.
  - Check for spread terminals and verify proper terminal tension.
  Repair any conditions that are found.
6. Reconnect all BCM harness connectors. Be certain that all harness connectors are fully seated and the connector locks are fully engaged.
7. Reconnect all in-line harness connectors (if equipped). Be certain that all connectors are fully seated and the connector locks are fully engaged.
8. Reconnect all related component harness connectors. Be certain that all connectors are fully seated and the connector locks are fully engaged.
9. With the scan tool, erase DTCs.
10. Test drive or operate the vehicle in accordance with the when monitored and set conditions.
11. With the scan tool, read DTCs.
  Did the DTC return?
  
  Yes
  - Replace the Body Control Module (BCM) in accordance with the Service Information. Refer to MODULE, BODY CONTROL (BCM), REMOVAL .
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  No
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  - Test complete.