RangeRovers.net Forum banner

1 - 9 of 9 Posts

·
Registered
2002-2005 Range Rover MkIII / L322
Joined
·
887 Posts
Discussion Starter #1
Hey all. I’ve run the search, and am fairly sure the potentiometer in my TC shift motor has gone bad. Just wanted to bounce it off everyone and see if you have the same consensus before I spend the $1k for a new one.

The symptoms started with the constant dinging accompanied with the message “transf case natural”. It was driving fine when that started. My wife was driving it on the freeway when it first happened. She said it eventually slammed, like dropping into first gear, and then she got the “trans fail safe” message. By the time I got to it, it had a Christmas tree of faults. I cleared them all, with these exceptions that would not clear:

Transfer case actuator noise
Instrument cluster transmission communication failure.

After clearing the faults, it will drive fine for a while, then starts the dinging with the transfer case neutral message, an occasional “high range” message although the range switch is never touched, and finally followed by the trans failsafe. The interesting thing is there are no allcomms faults for the transmission module, even after it goes into the failsafe mode. Since this has started, the low/high range switch is totally inop. Pulling the switch does absolutely nothing...no lights and no action from it. I was able to insert the fuse 37 to get the trans case into neutral to tow it home from Corpus Christi, but I had to cycle the ignition about 5 times to get the case to shift to neutral. It shifted back to high range immediately after the tow.

I replaced the battery and charged it fully...so low battery is not the problem. It was in the gulf salt air, right on the beach for almost 2 weeks when the problems started.

And that’s about it. So what o you guys think...TC motor potentiometer, or something else going on?
 

·
LEGACY VENDOR
Joined
·
2,369 Posts
The ‘actuator noise’ error message is certainly the most common when the shift motor potentiometer is faulty.







Phil
 

·
Registered
2002-2005 Range Rover MkIII / L322
Joined
·
887 Posts
Discussion Starter #3
Thanks Phil, your opinion eases the pain of the price a bit. I just ordered a new motor assembly from the UK. I’ll update once I get it installed next week.
 

·
LEGACY VENDOR
Joined
·
2,369 Posts
If you guys over the pond are sending off to the UK for replacement shift motors anyway, you may be interested in this business http://www.4x4lro.co.uk, who I’ve read positive things about from a couple of members on the forums over here, who re-manufacture the shift motors and replace the potentiometer with a sensor of a different design:

“Our aim was to seek a more rugged sensor than the potentiometer and we investigated alternative sensing technologies. Eventually, we identified the ideal sensor which we believe is the best, and most cost-efficient solution for the harsh environment to counteract vibration, and heat cycling.”

I emphasise that I have no personal experience of using them, and I don’t even know if they will ship internationally, but may possibly be of interest?

Phil
 

·
Registered
2002-2005 Range Rover MkIII / L322
Joined
·
887 Posts
Discussion Starter #5
If I have any more trouble with the pot, I will look into that rebuild. It sounds optimistic! I have had both a ford and a Chevrolet that used a similar electric shift motor for their transfer cases. Including the Rover, I have had trouble with the potentiometers on ALL of these cars. The problem seems to be that the pot spends 99% of it's life on the high range position and the vibration and heat mechanically damage the pot in that position. The American cars were simple systems, so they just reach point where they don't shift anymore. The RR is so computerized that it causes many other seemingly unrelated faults.

I'd like to thank you, Phil, for all the help you have given me and others on this forum. This is my first transmission related post, but I have benefited immensely from the help you have given others here!
 

·
Registered
2002-2005 Range Rover MkIII / L322
Joined
·
887 Posts
Discussion Starter #6
I’ve got the new actuator from the UK, and will start the replacement tomorrow. Reading through the procedure in the RAVE, I have one question. There is mention of a “lead screw” that is not to be allowed to come out as you remove the actuator. Is that just another name for the splined shaft? In the picture it looks like they are talking about the splined shaft, but if so they are using multiple termininolgies for the same part.

In addition, since my actuator is shot, it is highly unlikely I will be able to get the TC into low range as specified in the procedure. If that is the case (no pun intended) should I ignore the procedure and turn the shaft to the low range position before installing the new actuator...or best to rotate the new actuator to match the position of the shaft?

OK...so that’s more than one question!?!
 

·
LEGACY VENDOR
Joined
·
2,369 Posts
The splined shaft and the lead screw are the same component.



I’m curious – which RAVE procedure states that the shift motor should be in the low range position when it is installed? I would have thought that it should be in high range, and that the new shift motor would be supplied already set-up in the high range position.



Phil
 

·
Registered
2002-2005 Range Rover MkIII / L322
Joined
·
887 Posts
Discussion Starter #8
Well, got the new actuator installed. This is absolutely the easiest job to date I have done on the RR. About 15 minutes from start to finish. Fortunately it shifted to low range just fine, and that was also the position the replacement actuator arrived in. It even came with a new O-ring. The hardest part was forking out the 880pounds sterling!?! The shifts are now very fast, where for the last 5 years or so they tended to delay frequently when changing ranges or going to neutral. So far no problems with trans failsafe or any of the other faults. Once again I assume they were cascades from the primary fault of the bad potentiometer.

Here is the procedure:

Actuator - ratio control
$% 41.30.03
Remove
1. Position vehicle on lift and select 'Low Range'.
2. Switch off ignition.
3. With neutral selected on automatic gearbox,
check that a fuse is not fitted in position 37 of
main fuse box. Remove fuse if fitted.
4. Raise the lift.
5. Ensure area to be dismantled is clean.
6. Position a container to collect any spillage.
+ CHARGINGANDSTARTING, REPAIRS, Battery.
7. Rotate multiplug anti-clockwise to release and disconnect from ratio control actuator.
8. Remove3boltssecuringratiocontrolassembly to transfer gearbox.

Thanks for all your help, Phil. You have helped so many of us...and we really appreciate you taking the time to assist!
 

·
Registered
2002-2005 Range Rover MkIII / L322
Joined
·
1 Posts
Dear RRPhil
I'm a guest on this forum and I'm from Europe. I'd like to send shift motor to 4x4lro for re-manufacture but all the contacts listed on their web are dead - looks you really know a lot about RR so I'm asking do you know if they are still in business or they closed it down or maybe you know somebody else rebuilding the shift motor? Thanks a lot for answer
Igor
 
1 - 9 of 9 Posts
Top