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 ACTIVE DTCS
1. With the scan tool, record the DTCs and any liftgate inhibitors.
2. Erase the DTCs.
3. Cycle the ignition off, wait 10 seconds, then cycle the ignition on.
4. Operate the liftgate several times.
5. With the scan tool, read the Active DTCs.
  Does the scan tool display; B1964-11-POWER LIFTGATE SENSOR SUPPLY - CIRCUIT SHORT TO GROUND?
  
  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 poor pin fit.
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
INSPECT THE POWER LIFTGATE DRIVE UNIT
1. Disconnect and inspect the Power Liftgate Drive Unit harness connector. Clean and repair if necessary and repeat step 1. If the connector is okay, continue testing.
2. Erase the DTCs.
3. Cycle the ignition off, wait 10 seconds, then cycle the ignition on.
4. With the scan tool, read the Active DTCs.
  Does the scan tool display; B1964-11-POWER LIFTGATE SENSOR SUPPLY - CIRCUIT SHORT TO GROUND?
  
  Yes
  - Go To 3
  No
  - Replace the Power Liftgate Drive Unit in accordance with the Service Information. Refer to DRIVE UNIT, POWER, REMOVAL .
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
ISOLATE AND CHECK THE (Q203) POSITION SENSOR SUPPLY CIRCUIT FOR A SHORT TO GROUND
1. The ignition must be off when checking a circuit for continuity to ground.
2. Isolate the circuit by disconnecting the Power Liftgate Module C1 harness connector containing the circuit being tested. Note: Use the wiring diagram as a guide to follow the path of the circuit.
3. Connect the negative lead of the DVOM to a known good ground.
4. With the positive lead of the DVOM, probe the circuit being tested at the component harness connector and check for continuity between the circuit and ground.
  NOTE:
  There should be no continuity between ground and the circuit being tested.
  
  Is the resistance below 10K Ohms?
  
  Yes
  - Replace the Power Liftgate Module in accordance with the Service Information. Refer to MODULE, POWER LIFTGATE CONTROL (PLGM), REMOVAL .
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  No
  - Repair the (Q203) Position Sensor Supply circuit for a short to ground.
  - Test complete. Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .