A late arrival to the forums, but an educated auto shop owner and I highly suspect connectors at differential- read on. My GT started to give the infamous "check limited slip differential" warning, could be canceled (main message cleared, small warning triangle persists lower left of cluster) initially, but grew to a point that the warning remained where the car icon should be and would not clear. Pulling faults with a new and updated Autel scan tool we use here for quick testing found a can network communication fault: C1869.86. While a defective part can possibly cause this fault, for instance the network connection internally at the motor could be the cause, but this is unlikely. I racked car, dropped panel that covers the rear differential area - comes off very easily with 8- 10mm skews and one captive 13 mm nut in the center to position panel to ease install. I found a total of 5 junctions/ connections to the various sensors and TWO motors at differential. I disassembled connectors and made a visual check of the pins- all ok and none were spread open indicating lack of tension. I reassembled everything and I was good for about 100 miles, then everything re occurred. clearing the fault had no impact as to whether it came back on instantly, or after 10 miles. Re racked, removed panel- looked closer. What I found was that on the connections at both motors mostly, and to some extent at other connectors, is you can move them in and out, and actually rock them slightly right to left, even when fully seated. The connectors have power, ground for motors, but they also contain the network wires for communication. Any movement in the connector will cause the pins move slightly inside the connector, causing friction/ movement between the pin and receiving socket- this will equal noise on the network. No go- wont work- ever. I disconnected all connectors to include the one three pin network pressure sensor on the top of housing (same harness), and applied contact cleaner for electrical connections to all pins. I then reconnected all connectors, and installed zip ties to the loosest ones, both motor connections and the one connection about half way up the case- its a junction. two were easy, one a little tricky, the motor on the left side. I can send pics if anyone wants to see how I did them. Once complete, I cleared the faults and headed out for a test drive. Keep in mind, I drive this car hard, and the issue was to the point that it would set as soon as car was driven. With no mercy I went and ripped up my favorite old paved logging road, multiple steep tight hairpin turns, ect. Guess what- no light. I have now driven about 250 miles- no light. I re scanned vehicle for possible pending faults- none!! As I mentioned early on, a connection is far more probable than a part in a case where a network or communication fault exists. There will be a handful of failed motors, sensors- thats inevitable, but these connectors will need addressing by Kia. I will update if anything changes as I plan on keeping this one for w while! I also suspect eventually Kia will figure this one out, and do an updated harness with better connectors, but for now the zip ties saved the day! Greg H
