Diagnostic Test

WARNING: This page is about a different car, the 2020 Jeep Cherokee. However, it is still accessible from the selected car via links, so may be relevant.

CHECK FOR AN ACTIVE DTC
NOTE:
All key fobs used with this vehicle should be present during this test. In pursuit vehicles, the most probable cause that sets this code is the RKE transmitter being pressed over 1024 times when it is out of range of the vehicle and loses synchronization with the rolling code in the RFHM. If the DTC is active, drive vehicle above 5 MPH; and then verify the DTC has changed to stored. If the DTC is stored, the concern has been fixed. If the DTC remains active, reprogram ALL key fobs to the vehicle first using the diagnostic scan tool.
1. Use the alleged inoperative key fob, cycle/press (if equipped with Keyless Go, the KIN button) the ignition on.
  NOTE:
  On the Passive Entry Keyless Go (PEKG)/Keyless Ignition Node (KIN) system, using the rounded end of the key fob to press the Start/Stop button can cycle the ignition even if the battery in the key fob is inoperative or there is a failure with the Low Frequency (LF) Antennas.
2. With the scan tool, read RF Hub DTCs and record on the repair order.
3. Press the lock/unlock button of the alleged inoperative key fob several times.
4. With the scan tool, read RF Hub DTCs.
  Is the DTC active?
  
  Yes
  - Go To 2
  No
  - The conditions that caused this DTC to set are not present at this time. The key fob may have already been re-synchronized by being in the vehicle while it was being driven. Inform the owner of the most probable cause for this code to set and therefore causing the key fob to be inoperative.
CHECK THE KEY FOB
1. With the scan tool, erase the DTCs.
2. Turn the ignition off.
3. Put the inoperative key fob in the vehicle.
4. With the good key fob, start and drive the vehicle above five miles per hour for one mile.
5. Turn the ignition off.
6. Operate the inoperative key fob in all functions several times.
7. With the scan tool, read RF Hub DTCs.
  Is the DTC active?
  
  Yes
  - Go To 3
  No
  - Test complete.
REPROGRAM OR REPLACE THE KEY FOB
1. With the scan tool, reprogram ALL existing key fobs used with this vehicle.
2. With the scan tool, erase the DTCs.
3. Turn the ignition off.
4. Operate the previously noted inoperative key fob in all functions several times.
5. With the scan tool, read RF Hub DTCs.
  Is the DTC active?
  
  Yes
  - Replace the key fob and program using the scan tool.
  No
  - Test complete.