Transfer case motor replacement on a 2008 Jeep Grand Cherokee brought to us by a client from Vancouver is our latest featured service.
The transfer case motor is the actuator unit that changes this Jeep’s four wheel drive system from high range to low range or into neutral. This vehicle came to us after the “service 4WD system” light came on during a recent trip which involved some off-road driving and shifting of the transfer case.
When a dash warning light comes on we must diagnose the cause of the concern in order to find the defective component. Diagnosis is a systematic process. Contrary to popular belief we can’t just plug in a computer and have it tell us what component is at fault.
This transfer case motor replacement is the perfect example of the diagnostic process. Our first step is to plug in our diagnostic scan tool to the vehicle and access the relevant module. We then scan for stored trouble codes. On this unit there were two codes: C1405 (transfer case range position sensor circuit high) and C140F (transfer case range position sensor erratic performance). Armed with these codes we then proceed to the repair information which lists the relevant tests. After performing these tests we found the position sensor itself was defective. The sensor is located inside the transfer case motor and is serviced as part of the complete motor. Unfortunately the part is rather expensive but on a positive note, the labour is simple.
Most modern four wheel drive trucks use these transfer case actuator motors because it allows for simple push button operation and automatic shifting. In the past transfer case shifting was accomplished with a floor mounted lever. While it was crude it was a simple, trouble free component. Unfortunately it is found in very few trucks these days.
For more information on this Jeep Grand Cherokee click here: http://en.wikipedia.org/wiki/Jeep_Grand_Cherokee
For more information about transfer cases click here: http://auto.howstuffworks.com/four-wheel-drive2.htm
