Lost Lake

Forgive me if this has been solved, but I haven't seen this problem before...

Going down the road in my 06 3500 the 4 wheel low light flickered a couple times. I stopped for fuel and the light came on and went off then the 'service 4 WD' light came on. I shifted to 4 wheel and it went into 4 high, then 4 low, then it wouldn't come out of 4 low, finally did, then I drove in 4 high for a bit, then put it back in 2 WD.

The light 4 low light flickered a few times on the way home and I was scared she'd jump into 4 low while I was doing 70....

When I turned in the driveway I felt it was in 4WD high.

I got out and scratched my head, figuring I'd check into this in the morning. I opened the driver's door to put something inside, closed it and the 4WD actuator moved. I opened and closed again and it cycled again. I crawled under the truck and felt it, a little plastic shelled thingy on the transfer case, and it cycles when the driver's door is opened and closed.

Any idea what the problem is?

Lost Lake

I can see why this isn't a well replied to topic! I have learned a bit, still haven't found the problem though. Just looking online to see where to start.

It seems the 4wd shift circuit is downstream from the air conditioning high pressure switch and if the switch is going it could affect to voltage to the 4wd.

Also the TIPM houses all the circuits for these systems and there could be a problem there.

Or there could be a chafed wire running around my transfer case.

Or it could be the 4wd selector switch.

All of these have caused the same symptoms that I have.

One poor guy replaced his servo motor, switch, TIPM, transfer case, and then his wiring harness before he solved the problem.... I DON'T want to be that guy....

Shorts

The thing about opening and closing the door causing actuation, start searching for a short circuit/chaffed wire.

jhenson

I don't have your exact symptoms but as of late when I go to put mine in 4wd (I try to use it at least once a month just to say that I Have Used It.....makes me feel better) it doesn't directly engage. I turn the dial to 4lo and it stops in 4hi with the 4 lo light blinking. Once in 4lo the same light still blinks but it won't go to 4hi......nor will it go back to 2wd.

About 3 weeks ago I'm pretty sure my neighbors were scratching their heads and saying "That dude needs to be put into a straight jacket" because the darn thing refused to go back to 2wd and I pulled forward and backed up in my driveway for about 20 mins trying to figure out what was going on. I got under the truck (while it was running) and unplugged the connections and I got a ding and a light telling me to service the 4wd. Shut the truck off and plugged connections back in and when I turned the key on I heard it go back into 2wd. Haven't had time to mess with it since but would surely like to know whats going on. Please keep us posted.

murrayrg1

I've worked on 4x4's for over 30 years and the worst thing that the engineers did was make the electronic engagement for the 4x4. There are only a couple of different manufactures for transfercases but they all seem to have the same problem and that is shifting in and out of 4 high and 4 low. If you were to read the manuels and it doesn't seem to differ if its ford,dodge or gm the perfered method is to shift from 2wd to 4wd and this can be at slow or high speed. However to go from high to low or low to high you are suppose to shift at an extremely slow 4-6 mph and usually with an automatic you are usually instructed to shift the transmission into neutral when shifting from high to low. To go from low to high just reverse the procedure. I find this works about 20-30 percent of the time.
One thing that does sometimes help is to shut the vehicle off and then start it again and this also works about 20-30 percent of the time. If that doesn't work then it is forward and reverse until it goes into the proper gear. As far as the service 4x4 light coming on this is a very common problem especially with jeep grand cherokees and even the dealers scratch their heads on this one. One thing that one can do is too check your connections at the transfercase and in some applications and if you can I have sometimes removed the sensors from the transfer case and cleaned them. As far as worrying about going from 4 high to 4 low at high speeds I have never in my time heard of anybody actually accomplishing that feet as it is hard enough to do it at low speeds as you know.

jhenson

Thanks for the above info ^^^^. Just curious to know if you can convert and electronic shift t-case to manual or would it screw with the electronics and keep the dash lights on all the time? I'm extremely partial to manually shifting a t-case but for some reason in '03 when I purchased my truck the dealer informed me that it wasn't an option....e-shift only.

5.9MegaC3500

Hey I know this is a late reply but I had the same issue as you with my 07 mega cab. Over 8-9 months a lot of work was done to my truck by a few shops in order to try and fix the problem. But a small connector under the TIPM is what finally fixed the problem, the part # is 68020745AB and the connector cost me $80 CAN. After 50 000 miles the problem came back once but I put some dielectric grease in the connector and it has not come back since. This problem only seems to affect 06 and 07(manufactured before December 2006) 2500/3500 mega cabs with the 5.9 engine usually with the Laramie trim.

Hope this helps

Asher

I've been traveling down this road for 3+ years now, I think the biggest problem is that its not a BIG PROBLEM (meaning not happening to a lot of trucks)... Mine has had the dash switch replaced twice, shift motor replaced once, control module replaced twice, and I think the range sensor replaced once... All this was done while the truck was under warranty, but nothing has fixed the problem and it is a random problem...

It got to the point that I just pulled off the range sensor, marked the shaft and case for each position 2h-4h-n-4l... Then I placed a piece of clear plexiglass over the hole to use as a window and seal. So to operate the modes I crawl under the truck, pull off the shift motor plug and use my cordless drill battery pack and bump the motor to the correct mode I need.

The best possible fix I have found is someone fixed their problem by tightening all the connections on the large plug above the transmission, theory is the individual wire connections are not tight and corrode or loose contact... In a couple weeks I am pulling out my tranny, and when I do I will clean and tighten the connections, I will let you know what the results are...

Good luck...

5.9MegaC3500

The connector under the TIPM is what fixed it for me, I also found this
TSB 03-001-07

John Hughes

I had the same issue with my truck randomly shifting itself in and out of 4 wheel while driving or even when the truck was off I recently had tranny work done so I assumed it was a wiring issue so I checked resistance from the tcase motor harness to the tipm harness and it all checked out so I pulled the board from the tipm and it visually checked out good as did the connector so I replaced the tcase motor and it fixed the issue.