thewhirls

OK, folks, I have begun to solve question #1 above reagarding the stuck transfer case (since I could find nothing relevant in this or the Touareg forums) by monkeying around under the car. Here is what I have learned:Yes, the stepper motor on the transfer case controls BOTH the going in and out of low range AND locking the center differential.I figured this out by attemepting to swap the known good motor from my V10 Touareg (which is shaping up to be the far better vehicle between the two) to the Cayenne Turbo. I took it off the Touareg when it was in high range. When I went to put it on the Cayenne, I could see that the shaft keyway was not going to align with the motor's keyway (sicne the Cayenne was stuck in low range), so this is how I knew that this stepper motor controlled hgih and low range. I had to grab the shaft coming out of the transfer case with some channel lock pliers and rotate it counterclockwise (looking toward the shaft) about 90 degrees and lo and behold it clunked into position to line up with the stepper motor. So, figuring the good motor from the Touareg would operate everything just fine, I lowered the car, fired it up, (no more fault light and hgih range working now) and operated the switch to put it in low range, lock the diff, unlock the diff (so far so good--no warning lights), and.... it would not go back into high range. Warning light back on. Stuck again, even with the good stepper motor. So.... back up on the lift, remove the stepper motor again, rotate the shaft manually with the pliers counterclockwise into high range again, rotate the motor shaft to align, and bolt it all back up. I'm afraid to try it again. One thoguht I had is that it is just stiff from lack of use (prior owner didn't use low range, it seems) and that after these couple of manaul movements it might work eventually. But I'm too tired to try it again and go through the above process again right noiw. I think I'll look under the passenger seat instead and see if there are any wires amiss.So... I still don't know why the Cayenne won't operate the stepper motor from low to high range, but it operates it fine in every other operation. Next stop: the control module under the passenger seat and its attendant wiring!Useful lesson: stuck transfer case can be unstuck manually. Taking the stepper motor off is really easy. Three 10mm-head bolts and two 8mm-head bolts. Two wire connectors. One pair of big channel locks or vice grips with good teeth to engage the splines on the shaft without damaging them.

Are you any further forward with the stepper problem? I have a cayenne which disengages drive completely in the transfer box whilst moving.

What electrical problems did you have?? I have some real strange things happening on my Cayenne which i believe are linked to my wet floor.

It was a bit of a cascade of errors - I am not sure if it was one problem that was causing a chain of events, but the worst was a disk proportioning error, along with ABS failure, shifting problems, and full PSM failure. The car would start, but the shifter would lock in park. In the end I had to remove the panel and manually disengage the lock to put it into gear and move it.

A single fine wire with a corroded connection on the passenger side was causing all of this. But I have it feeling it could have been related to wheel sensors or something - a critical part of the system that caused everything else to fail. As soon as I cleaned it up and reconnected it, everything pretty much went back to normal.

Good luck - hope that helps out a bit.

Thank you ever so much, i'll have these checked and let you know what happens.

For me, the wet foam caused corrosion of some of the connections inside the wrapped wiring, eventually causing a real cascade of electrical problems that were a challenge to correct. The carpeting itself appeared completely dry - it was troubleshooting the electrical failures that eventually led to me pulling back the carpeting and finding the water.

What electrical problems did you have?? I have some real strange things happening on my Cayenne which i believe are linked to my wet floor.

Thanks for the reply, the battery is only a few months old.

I believe the temp problem could be a wiring issue, it's almost like something is arking the way the meter reads.

I think it's the transfer box as when i lost drive, i stopped and flipped the 4WD switch backwards and heard a crunching noise leading me to believe the gearbox was still in drive. Once i placed the gearbox in neutral i could flip the 4WD system switch backwards with no crunch.

What is a stepper motor?

Hi All,

Before i start - great forum, i've been a spectator for a while!

I have a 2003 Cayenne S ( pic attached )and have the following problems which gathered over the years, these are -

* Oil temp / level sender problem which results in engine too hot message displayed, i've had changed the level sender and the temp sender, interestingly the oil temp gauge on the dash is extremely erratic sometimes but generally just slowly rises into the red, sits there for a minute or two then returns to zero and stays there.

* The car shifts into neutral on its own whilst in motion - This has happened 3 times in 3 years but twice last week. The transfer box is changing into neutral on it's own - i've noticed before it happens the red light on the 4wd system button thing on the centre consul flashes, then it just goes into neutral. I stop the car without switching the engine off and flip the off road selector thing backwards, this re-engages drive.

* The other problem i have is that the car shudders when i accelerate at low revs which i believe is common. It's just had 8 new coil packs but although better the shudder is still there.

The car is purely a 2nd car for us now but my family travel in it so i do want it sorted, unfortunately in live in a very secluded area of the UK and really need to travel to a specialist however this is something i will do in the next couple of weeks, my problem being i doubt if they can fix the problem in one day ( which is all i will have )

Any pointers / advice will be greatly appreciated!

Rob