Realize this is an older thread, but did anyone have any further explanation/outcome on this? Let me add my own issue to the pile, and do my best to summarize what other posts I've found on here that are close to (but not quite) the same.
I did about 800km (round trip) today, mostly on the highway, and for the first ~750km nothing was out of the ordinary.
On the home stretch, my cruise control (set at about 80km) dropped out unexpectedly. I didn't think anything of it (thought I could have accidentally killed it) and resumed. A few seconds later, same thing.
I continued along without cruise, chalking the cutouts up to the Jeep telling me not to use cruise control with water on the road, when I noticed a light bucking for no apparent reason. By that I mean, while doing anywhere from 70-90km/h the Jeep's motion would intermittently and ever so slightly 'stutter'. There didn't seem to be any justification for it, or any indication it was happening beyond what you could detect from those small, tremor-like jerks.
A few more of these happened, and then the ESC light started spazzing in short bursts.
I alternated between cruise and no cruise for a few more km trying to determine if I was imagining things (I was tired, it had been a long day of driving), and trying to see if a particular gear (4th or 5th), or a particular grade of highway or amount of water on the road was responsible.
I think I found the bucking (like a momentary loss of power/acceleration) seemed to occur more often when the engine was under load of either acceleration or an uphill grade, though I wasn't really sure. The intermittent bucking did occur in both gears and on anything from dry pavement to light puddles on the highway (nothing I would expect to hyrdoplane on).
At this point, I considered pulling over and getting a tow but it's a Saturday night of a holiday weekend (nothing open Monday) and I fly to Europe for two weeks on Monday anyhow so I thought since I wasn't getting a MIL I could justify driving then last 40km.
Moments after convincing myself of that, more bucking and my ABS, then ESC lights on solid. Still not a MIL (just a sinking feeling), so I keep driving. I try switching ESC off but the button doesn't respond. A few km more, no more bucking and the ABS and ESC lights shut themselves off.
I try killing the ESC again and this time I successfully get the ESC OFF light. A few km more, no bucking, and I switch the ESC back on. A few km more, repeat bucking, ABS, ESC, sinking feeling...
I find the next pullover and try to and figure out WTF.
I do a quick walk-around and nothing appears obvious. No flats, nothing visibly broken, so I grab my flashlight (it's 11:30pm and pitch black) and crawl under to check the four wheels - all the brake lines and other components look fine, nothing hanging. I grab my tire gauge and check the pressures. DF, PF and PR are all at a little under 36. DR was a little under 35 as I had a puncture last week (but caught and changed it before it deflated thanks to the TPMS... damn thing actually made up for being finicky about pressures in the past by saving a tire!).
I didn't think a pound difference in one tire would be enough to throw off the ESC (particularly since there was no TMPS warning after all) but I aired down the other 3 to the same level and, after confirming on the Jeep iPhone App that the ABS light was safe to drive on until you could see a dealer, figured I'd head for home. When I turned the ignition on again, the ABS and ESC lights stayed solid after the test flash. I didn't have any bucking the rest of the way home, but obviously I wouldn't as the ABS light would mean the ESC is disengaged... and it sure sounds like an ESC issue.
So, from what I gathered with a few hours research on the forums once I got home, I checked to see that the battery cables are seated properly as others have suggested fixed a similar issue:
Another thread suggests a similar issue with the ABS/ESC in '12 rubicons is the result of certain mods causing electrical issues with the sway bar disconnect:
I don't drive a Rubi (I'm a stock Sport B, save for the factory steps I snagged on a rock and bent my front quarter panel where they mount to the body(!)... lesson learned, rock rails on order) so that doesn't seem directly relevant to me.
There's also cases where wheel sensors are damaged as the result of a lift:
That thread also suggests "the newest flash" (as of January '12, which is before my Jeep was even built) fixed the issue:
Another thread talks about faulty wheel speed sensors in previous model years (caused by something other than a lift):
I checked for DTC codes using the technique posted here:
and found the ABS and ESC codes, as well as the ETC (electronic throttle control) and the MIL (more on this later...)
Since I'm not going to be able to drive the Jeep let alone get it to the dealer before mid-July, when I do get home I'm hoping to be armed with as many details on the circumstances and outcomes of those of you who have been through this, particularly with a 2012.
Originally Posted by pkmcd99
Is this a 2012 Jeep you speak of??
Originally Posted by pkmcd99
Read your profile, so yes your 2012 may have PCM issues!
Do you know specifics about PCM issues occurring in 2012's?
Originally Posted by ajleemax800
I have a 12 with 30k on It it just started to do the same thing.
How did this turn out for you?
Is there any chance I'm going to get trouble on warranty claim to fix this if I'm completely stock? Or does anyone know of a TSB for the ABS or wheel speed sensors in 2012's/are there enough of us with a similar enough issue in the same model year to argue it's absolutely a defect?
Last time I used the forums like this before going in for dealer service I wound up diagnosing in advance that I had caught the dreaded cooling system sludge build up epidemic of the 2012 (and 2013?) model years.
Beginning to think my Jeep honeymoon is over... just when I was starting to relax and enjoy the topless weather without worrying I was driving a ticking time bomb...
PS - As far as the ETC and MIL codes I just discovered during this troubleshooting, I do remember throwing these days after I took delivery of my Jeep. I pulled away from a 4-way stop and stalled causing the dash to light up like Christmas with indicator lights. I had not yet studied the idiot lights for this vehicle, beyond scanning the owners manual and iPhone App so I pulled over and killed the ignition. I decoded the ETC symbol and the dreaded MIL. I was terrified that the MIL could mean "serious conditions" with my brand new Jeep, but when the MIL didn't stay on through the next driving cycle like Jeep docs warned I just chalked it up to what happens when you stall.