Transfer case shifting 4WD to $WLock on its own
 

My 08 hemi started shifting into 4 lock on its own, from what I can determine this was a problem on older durango's. Sometimes while driving slowly sometimes while not moving at all. It would not shift into 4 Lo at all. After a little searching I found the most common remedy was to disconnect the transfer case motor. It does leave the SVC 4WD light on but now I don't have to worry about my wife getting stuck somewhere. One repair that sounded reasonable was to replace the front control module, noting it controls the TC motor.
About 2-3 weeks ago the actuator for the rear HVAC controls started clicking every time I unlock the doors. Can this be connected to the front control module?
Maybe someone here with more electrical/mechanical knowledge than me can help.
While I don't think I've used 4Lo since I bought the car new, I still do not like the idea that the connector is only partially protected from the elements and may cause further problems if water gets into it.

Hi billdc,
I'm sorry to hear about this. I was unable to find any TSBs that might address the concerns you presented. If you would like assistance in scheduling an appointment with your local servicing dealership, I'd be happy to help!

Thank you for looking for a TSB. With some of the complaints I've read regarding multiple service attempts that did not resolve the issue.
Also I feel that the trouble with the transfer case and rear HVAC actuator and door locks may be related by a control module. I would like to do a little more homework regarding the possible link, (are they are controlled by the same unit)? If you have any knowledge regarding where I could start that would be great.

Have you spoken to a technician regarding your questions?

No I have not yet. I like to have some idea of the problem beforehand. In the past I have blindly agreed to repairs that only managed to separate me from my money and did not fix the problem until the second or third "repair". I am not in a rush at this time and will take some time to learn about the control units involved. If its something I can repair, great, if not I have no problem paying someone who has the tools and facilities to repair the problem in a timely manner. I just have to find time to do the research.

Did you ever get this figured out?
 

Mine is doing the same thing.

What a coincidence. Mine has started doing this as well. Was going to ask about it myself.

I started hearing an odd sound when vehicle wasn't even running. Just parked and locked up. Sounded like a metal on metal slicing sound and then a "thunk". Didn't know what it was at first. Then I turned the key on (engine off) and rotated the dial and realized it was the transfer case. I also started seeing the "SVC 4WD" light on the dash intermittently while driving.

Today while slowing down in a parking lot, it jumped in to 4 Low. I personally think it may be the dash switch as I would rotate through the settings and hit the dash below it and it would stop for a while. I'm going to try and disconnect it first to verify.

I think I've read about this before, being the Transfer Case Motor/Module?

Well I disconnected the switch and now it shows "SVC 4WD" continuously. I've already ordered a replacement switch and I'm going to try it first. Any idea on material that talks about the motor/module, location and part number? Thanks.

Well, disconnecting the switch does not stop this. Today when I hit the unlock on my remote, I heard the slicing/thunk noise again. Guess it's on to the motor which is going to suck as you have to remove the front drive shaft to access the motor. :(

I thought you could get it without doing that, but I might be wrong..

The video I watched (which was for a RAM truck) showed driveshaft having to come out. Then again, it doesn't show the cross member sitting right in the middle of the transfer case either. I crawled up under the truck and looked at it. I "Think" I may be able to remove the motor without removing the driveshaft. Going to be a tight fit. Even getting to unplug the harness was difficult. I have ordered a motor and will attempt to replace when it arrives.

Good Luck!

I disconnected the cable from the transfer motor. I filled it with dielectric grease and wrapped it in plastic and electrical tape. I know have a service 4WD light on the dash. I not not have the option of 4LO, but I never used it. The motor will not work without power. I stopped looking for a solution to this problem. Hope this helps.

That's a good work around, didn't think of that. So you have AWD and 4HI, or are you just in AWD only? I know you said 4LO is not an available now.

When you disconnect it, the motor is stuck where ever it was when you disconnected. So if it was in AWD, it says in AWD. You cannot select 4HI or 4LO. I also thought of just disconnecting the motor wire but you don't have much space to work with and the cable needs to be tied up so it doesn't hang down in the driveshaft.

I have a motor on order. Once it gets here, I'm going to try and replace. After I'm going to need to do a transmission pan/filter service as I suspect the leaking pan is the cause of the motor failure. The shop I had do it last apparently did it wrong as it has had a slow leak from the pan ever since. :(

Good Info, thanks!

I'm due for Trans services as well.....I might get the front and rear diffs done at the same time, as I haven't done them in about 25K.

Yes it is stuck in AWD. But I was able to wire tie it up and I check it occasionally. Surprisingly it does seem to be holding up well.

If you are going to do the transmission and front and rear diffs, you might as well do the transfer case at the same time too.

Biggest issue I have with just disconnecting and tying it up is will it pass inspection? In Texas they require inspections. Even though it has nothing to do with the actual motor or emissions, I worry they will fail with the dash light on for "SVC 4WD".

We have inspection as well, I take it to my regular mechanic so maybe he just ignores it. In NJ the inspections are done at a state run facility and they might not be as friendly. I know any sensor alerts will keep it from passing inspection, but I have not had any trouble with the 4WD light.

Good to hear. Since it's not an actual "Trouble Code", hopefully they will ignore it here as well. Upon further inspection, it looks like the motor may be more difficult to replace than I thought. It has a splash shield that wraps around the motor casing. Think this is why it says to remove the drive shaft. I'm hoping I can pull the shield down far enough to slide the motor out. Otherwise I will either have to remove the driveshaft or pull the cross member that holds the transmission so I can remove the shield. :(

Yeah, probably. I never switch out of AWD, so wasn't sure if it was necessary.....but suppose it wouldn't hurt.

Per the manual, if using it for "police, taxi, fleet, off-road or frequent trailer towing" to change out every 60,000 miles. Doesn't list for normal use though. Odd.

When I got mine back in 2014, I went ahead and switched out all fluids to Amsoil. So I went ahead and did the transfer case as well. Uses ATF+4.

So I replaced the transfer case motor today. Although I did manage to do it without removing the drive shaft, I did have to remove the transmission mount and splash shield for the motor. I tired just removing the bolts that hold the trans mount to the trans and lifting the trans to slide out the shield, but with all the curves in it which wrap around the motor, this was impossible. I had to remove the bolts that hold the trans mount to the cross member as well to pull the mount out first, then slide the shield over to drop the motor.

Bad news is that for some reason the plug for the motor just didn't seem to want to plug in all the way on the new motor. Therefore I am still getting a "SVC 4WD" light as I suspect it is not making full contact. Not sure what is going on here. Looks like the plug on the new motor is slightly longer and won't allow it to seat fully. With the Texas heat and having to work in a gravel driveway, I think I'm done with it for a while.

I did this job today on 2007 Aspen. After supporting tranny I dropped entire tranny xmember and mount as a single piece, making access to that heat shield a breeze. No advantage messing with driveshaft as the Ram guys do. Once xmember dropped job was straightforward. I decided to change motor after reading this was most likely cause. We'll see if I wasted my money or not. It seems like most people suggest to start at motor and work backward, checking connector for corosion, then wiring harness for damage, then module, and switch is last. I had no other symptoms on dash so I did not consider module- may have to have it reburned if problem persists.

I have the 07 aspen with AWD, Hi and Lo. So on Sunday I went somewhere and noticed the truck is in 4x4 lock but no lights on. Tried turning the switch to 4high lock and 4 low lock and nothing. Monday morning I started the truck and I had 4x4 lights and everything switched normally. Tuesday morning no lights again and no 4x4 again. Decided to get a new transfer case motor and just had a local mechanic put it in. I still have no lights so maybe it wasn't the transfer case motor. Although the old motor has this slopping around sound in there. What will be the next to check.....the front control module maybe? Any help would be appreciated.

First time here, but having these exact problems with my 2007 Aspen. Where you ever able to get it resolved? Thanks.

Hello,
It's probably going to be the transfer case motor. This has been discussed in multiple threads and across multiple forums I'm on. Seems to be a common issue for the motor. I did replace mine, but I went aftermarket and the plug seems to be longer and won't connect to harness properly so it's still not working as designed. However, it is no longer trying to switch on it's own so I've left it as is for now. I don't have a garage to work in so it may be like this for a while. I need to pull it back out and try to shave the plug down a little. Others have posted that replacing motor has resolved their issue. So I would start there.

Thank you for your quick response. The service team did in fact replace the transfer case motor, but it did not resolve the issue. They are still researching this, and hopefully, I will get some more information.

Have them check the front control module for corrosion on the pins. I disconnected mine several years ago and in PA it passes inspection with the light so far.

Thanks, will pass that along.

Have you read the codes on the body module?

My Aspen is doing a similar thing. The code came back that the low range sensor was out of voltage range. Apparently it runs on a 5 volt supply that feeds multiple sensors. If one of those sensors is out of range it could affect other sensors. The three fixes I read over and over were.

1. Unplugging the AC pressure sensor. I know it's weird but, it apparently can cause the system voltage to drop and push the voltage out of range.
2. Clean the battery.
3. Check the wires very very closely and look for any rubbing or exposed copper. It's apparently a common problem in other dodge vehicles with the same Engine and Transfer Case.

At any rate read the codes on the body control module. That's where the transfer case errors are stored.