I am having the same intermittent problems with a 2006 Commander 3.7l. Another problem is the Park Assist stops working. This vehicle belongs to a friend of mine and has had it worked on at three different Chrysler dealerships and two other automotive technicians over the last eight years.
Ignition switch has been replaced under warranty. I have removed and reconnected the connector with a very positive snap.
Final drive module has been re-flashed.
No codes present, pending, or historical when checked with Vgate OBD scan tool.
There must be some common connection between these functions.
Anyone have an electrical schematic they would be willing to share?
If your friend's park assist/back-up sensor stops working, it could very well be because it is bad and needs to be replaced.
Is the park assist sensor completely shutting down or is your friend getting some indication that has been disabled?
What color LED indicator lights is your friend seeing on the park assist sensor itself - if any, when this happens?
It's hard to give any recommendations when you leave out so many details in the description of the problem.
I had to have my park assist sensor replaced because it kept shorting out and disabling itself, but, I would receive an alert stating "park assist disabled" and I would have two or three Red LED's on the sensor itself, light up along with the normal amber ones. Also, instead of hearing the normal spaced series of audio tones when backing up, I would immediately get one continuous audio tone, just like the audio tone you get when you get really close to an object behind you while backing up, only I would get it as soon as I shifted into reverse, with nothing at all behind me.
Not that it's really relevant, but, here is a quick synopsis of the trials & tribulations I dealt with and what I had to replace when I bought my Commander - after actually finding out everything that was not working - or working intermittently, that I would classify as falling outside of normal maintenance
Had to replace my radiator cap and battery within the first 6 weeks of ownership.
The battery just completely died on me, without any warning or prior issues (while out in the woods no less). This may be classified as routine maintenance, but, it's certainly not something I would have expected to do within the first 6 weeks of buying a new "used" vehicle. The radiator cap wasn't sealing properly and would leak coolant when hot, I discovered this problem after about 3 weeks of ownership and finding very small puddles of coolant on the ground after being parked a couple of hours after driving. The coolant was almost clear, so, it took me a few days to figure out, that it was actually coolant I was looking at. I guess I still had in the recesses of my mind, that anti-freeze/coolant is green, LOL. What can I say, I'm old school.
After about 2 months of ownership, I had to replace the actuator motor on the Transfer case after getting the dreaded "service 4WD System" warning while trying to shift into 4-LOW which I was unable to do. That was about a $780 repair, when you add in the initial diagnostic trouble-shooting charge of $120.00. I found out after the fact, that my vehicle did not have the P73 recall (reprogramming the FDCM) done yet, which, as it turns out, was the fix for this issue. I submitted a claim for reimbursement to Chrysler and was paid in full within 2 weeks - there is a thread about this on this forum (I believe it is titled P73 recall) where I explained how to submit the claim for reimbursement to Chysler.
The radio display for the back-up camera video, would not display usable video from the back-up camera while backing up. This was an intermittent problem, when I first bought the Commander it worked fine, but within a couple of days, my radio display would no longer show usable back-up camera video, it would display it extremely dimly, so dim that the radio display almost looked completely black, as if it wasn't working at all. The radio display itself, for radio related functions, worked just fine. As time wore on, sometimes the display would display back-up camera video - and sometimes it would not - most of the time, it would not - and when it did decide to work properly where I could actually see usable video from the back-up camera, it would only be for very short periods of time. First, I replaced the back-up camera. This was the cheaper repair of the two repair options I had (replacing the radio was the other), and of course, it didn't solve the issue. Eventually I had to replace the entire radio - that solved the problem. A rebuilt/reconditioned radio from the dealership (which is all you can get now - they no longer sell them brand new) is still almost $1000.00 by itself - 900 and change as I recall.
Satellite radio did not work. Initially, I thought this was just because I didn't have an active subsciption that was paid for. However, after I called SiriusXM, gave them my radio information and enrolled and paid for service, I found out that the Satellite radio, in fact, was not working. I was still unable to acquire a satellite signal after numerous attempts. The Jeep dealership found after troubleshooting, that the cable running from the satellite radio, to the satellite radio antenna - which is routed up through the headliner to the satellite antenna on the roof - had a break in it. The Jeep dealership said that they found no evidence that anyone had ever removed, or tampered with the headliner before. So, explain to me how the hell that happened? I had to replace the satellite radio cable & satellite radio antenna, because you can not buy one component without the other. This was another $1000.00 repair job plus another $120.00 for the initial troubleshooting. Most of that was labor. The parts themselves, were fairly cheap.
Back-up sensor kept shorting out (symptoms previously described) and I had to replace the back-up sensor. This is the one problem that I know that happened after I bought the vehicle. I didn't experience any problems at all with the park assist/back-up sensor until I had it for about 6 months.
Once I had all these issues fixed to where everything was working properly, then I was finally able to focus on maintenance, and eventually upgrades.
Looking back on it, it was a long & expensive road to get to this point, but, I feel like it will be well worth it in the long run - I guess mainly because my Commander is bought and paid for and I have no plans on getting rid of it.
I think my experience is a prime example of what happens to an otherwise nice vehicle, when routine maintenance is neglected and/or the previous owner chooses to ignore things that don't work properly, as opposed to getting them fixed when the issue occurs. Or when you have a previous owner who just is not that observant.
The one thing I find odd is, that in my case, the previous owner was the original owner - which means she had a bumper to bumper lifetime warranty as I understand it - so, why not get this stuff fixed?
Maybe I was just lucky (sarcasm) and all of this stuff went to pot, right after I bought my Commnder - but I highly doubt it.
I believe most of these problems were preexisting when I bought her.