HELP! ... 2016 Jeep Cherokee
Need help diagnosing a strange electrical/network issue on a 2016 Jeep Cherokee KL after replacing the power liftgate.
Original issue:
The power liftgate would open a few inches, then automatically close. I disconnected the battery for ~10 minutes to reset the system but it didn’t help. I inspected the wires going to the liftgate and all looked good. I then replaced the motorized liftgate strut which had a module inside it with a used OEM unit from another 2016 Cherokee. After replacement, the liftgate started working perfectly again.
Immediately after driving the vehicle:
- Odometer started blinking continuously
- Driver-side master window switch stopped controlling:
- Driver window
- Front passenger window
- Passenger window still works from passenger switch
- Rear windows still work from driver window switch
- Everything worked perfectly before the liftgate replacement andbattery disconnect
Diagnostics/troubleshooting so far:
- Ran multiple PROXI alignments using AlfaOBD + VLink
- PROXI completed successfully every time but it did not fix the blinking odometer.
- I then went over the fuse's in the engine bay and pushed down on all the fuses (not sure what possessed me to do this but the next PROXI alignment worked.
- Blinking odometer is now gone after PROXI
- BCM communicates normally
- Liftgate module communicates normally
- Passenger Door Module communicates normally
- Passenger Door Module has U0199 (“Lost Communication With Door Module”)
- AlfaOBD CANNOT communicate with the Driver Door Module (DDM)
Things I’ve checked/tested:
- Visually checked fuse F38 (good)
- Visually inspected driver door harness in rubber boot between door/body
- No visible broken wires
- Performed wiggle test on harness with ignition ON → no change
- Removed door panel and replaced DDM with another used OEM DDM from junkyard
- Same exact symptoms with replacement DDM
- Still cannot communicate with DDM after replacement
Additional notes:
- Issue started BEFORE touching the driver door panel or DDM connectors, so I don’t think I caused a pin/connector issue during diagnosis
- Since TWO different DDMs behave the exact same way, I’m starting to suspect either:
- DDM power/ground issue
- CAN communication issue between BCM/body harness and DDM
- BCM not waking/addressing DDM properly after battery disconnect/PROXI event
At this point I’m planning to:
- Verify power and ground directly at DDM connector
- Check CAN voltages/continuity on DDM CAN pair
- Inspect body-to-door harness connector more closely
Only problem is im not sure how to do these things but i guess ill learn. Would appreciate any advice from anyone familiar with KL Cherokees, Chrysler CAN networks, or weird post-PROXI/battery disconnect issues.