i recently purchased a 2002 ford explorer (v6, auto4 wheel drive). it had
28k miles on it. when i purchased it i had it checked by a trusted mechanic who said all systems, including the 4 wheel drive were go. now, a few months later i press the button to have it shift into 4 wheel drive hi or low, and nothing happens. then a week later it worked for a short time. i took it to a transmission place and they hooked up the computer to it and said the shift control modulater would not communicate with their machine. so they took out my shift control modulater, and put in a used one which did communicate with them, so they said it was my electronic shift control modulater which was bad. they then put mine back in and low and behold it worked again, for about a week. then recently i was away for 2 months, came back and it worked again for about a week and now nothing. how do i diagnose this problem. it sounds to me more like a short in the wiring than the modulater itself, but i don't know. and also if i could find a used one, should i put it in? and is this the correct term for the part? it sits on top of the evaporator on the passenger side, i ask this because every website i have looked on has no listing for it at all. i don't use the 4 wheel drive that often, but you want it to work when you need it. the chiltons manual i have says it is not a hard job to replace the modulator, what do you think? thanks- posted
17 years ago