serv 4wd mil, serv 4wd, 4wd unavailable Bought the Renegade Latitude in late 2015; the second day I had it the “SERV 4WD” MIL and “SERV 4WD, 4WD Unavailable” on the information center both displayed at start up.I took it back to the dealership; they looked it over and stated that there is nothing wrong it’s just a break-in type of a phenomenon. 2016 in early spring on several occasions “SERV 4WD” MIL and “SERV 4WD, 4WD Unavailable” lit up on the information center, dealer scanned it and found four (4) ABS codes, contacted STAR Tech Support and followed a battery of inconclusive tests, in pursuit of capturing the “SERV 4WD” MIL and “SERV 4WD, 4WD Unavailable” display live, they kept the vehicle a few more days, and finally witnessed the display, performed a few more tests as per Tech Support and concluded that the differential assembly will require replacement. The Rear Differential Assembly was replaced a few days later, followed by the RDM, but it could not be programed. After finding and repairing a broken Rear Differential Clutch - Motor Hall Sensor wire, circuit T332, they were then successful in programing the module and declared the vehicle "fixed". We drove home, first startup the next morning, the “SERV 4WD” MIL and “SERV 4WD, 4WD Unavailable” displayed; back to the dealership. In my situation we discovered that when the internal cab temperature was above 85°, the “SERV 4WD” MIL and “SERV 4WD, 4WD Unavailable” would display as soon as the engine was started, like clockwork. Also, I should note that the “SERV 4WD” MIL and “SERV 4WD, 4WD Unavailable” randomly displayed and went off after a single key cycle; as described by so many others in multiple forums. Back at the dealership they allegedly discovered that my issue was now being caused by a software programing glitch; occurring after they replaced the RDM 68247020AB Module-AWD Driveline, the FCA repair procedure directs the Tech to program the RDM which also happens to include updates for the DTCM and ABS modules; allegedly during the programing, the software installed to reprogramed the ABS created a conflict with the RDM and DTCM programed functionality. According FCA engineers, the only way to correct the problem was to install a new preprogramed ABS Module with a compatible (older) software version and not run the prescribed pending (newer) update that was causing the conflict. I knew that this was a desperate attempt at a resolution. The vehicle continued to display the “SERV 4WD” MIL and “SERV 4WD, 4WD Unavailable” after the module replacement. Unable to fix the problem or install current updates, I had enough, I no longer own this vehicle. I should also mention I have since, in an effort to reconcile, test drove a 2017 Renegade Desert Hawk; brand new with 7 miles on the odometer, in the dealership's back lot with the heater on, I switched it into snow mode. It wouldn't engage and the “SERV 4WD” MIL and “SERV 4WD, 4WD Unavailable” lit up. Really FCA - shame on you!