JK Computer Dies

[JayKay09]

Hi All,

Wondering if anyone has experienced anything like this:

Twice over the past 12 months my Jeep has 'died' appears absolutely lifeless except for the rear right indicator light which lights up. It doesn't blink it is just constantly on. No other lights or signs of life.

The jeep assist guy, same guy both times, did some tests that were inconclusive but resetting the computer did the trick. Mentioned it at the service after the 1st time but they found nothing.

All i have to do to 'fix' it is disconnect the battery to reset the computer but am worried this is a bandaid fix for a problem that could get worse.

Any ideas?

[jklad]

Originally Posted by JayKay09

Hi All,

Wondering if anyone has experienced anything like this:

Twice over the past 12 months my Jeep has 'died' appears absolutely lifeless except for the rear right indicator light which lights up. It doesn't blink it is just constantly on. No other lights or signs of life.

The jeep assist guy, same guy both times, did some tests that were inconclusive but resetting the computer did the trick. Mentioned it at the service after the 1st time but they found nothing.

All i have to do to 'fix' it is disconnect the battery to reset the computer but am worried this is a bandaid fix for a problem that could get worse.

Any ideas?

You under warranty still? Have read on the US forums about the TIPCM (basicly the combined computer & fusebox unit) failing & having to be replaced, & it's not cheap; the symptoms sound similar to yours. The fact that it needs a re-boot every now & again means you may just have a software issue that requires a reflash at the dealership (or you may even simply have a loose ground connector); they'll charge you a few hundred bucks for this, but still better than the several grand a new PCM will set you back. They should also be able to search for detailed error codes using their Starscan tool.

Also, have you had the battery tested? The JK's computer is very touchy & doesn't like even a slight drop in voltage, with strange things such as random horn soundings and wipers going on by themselves and other "Possessed Jeep Syndrome" symptoms often an indicator of a battery that may be on the way out or not charging properly (though by what I've read, the JKs alternator is one component on the JK that surprisingly is fairly bullet-proof). Most of the better battery retailers will be able to run a test for you while you wait. Since it gets pretty hot under the bonnet of the JK, the factory-fitted batteries (which are not great to begin with) tend to cook themselves & are commonly known to fail after only a couple of years.

[MightyMouse]

The JK battery isn't much good and quite a few people have had them just up and die virtually overnight ( mine did.... ) so .......... as its only a matter of time anyway why not fit a decent unit ?

Your problem sounds wierd but as others say batteries can cause interesting problems.

Also learn to read ( and note them down for the stealer ) the diagnostic codes off the dashboard - just in case anything gets logged.

Overall it might be a PITA now but if its get worse when its out of warranty it could turn into a nightmare. Perhaps call Jeep assit every time it stuffs up telling them what you've had to do just to get it "on the record" so to speak ?

[davidd]

yeah mate. get battery checked out. and check for any stored codes. any better quality workshop or auto sparky has a scantool which will read a can bus and has a chrysler extension. failing that it sounds like as mentioned before a software problem to me. if your laptop gives you trouble, you reboot it and all is fixed. same with your ecu. disconnecting the battery is the same as unplugging your laptop and removing it's battery. it clears the ram and resets it to it's default condition before the error. my guess is that there's a minor software glitch that appears every so often, randomly. a re-flash of the software could be helpful. just check the other things first. a battery fault should be fairly easy to pick. a slow cranking speed or a prolonged crank over at first start in the morning would give you an indication of a poor battery. other than that a prpoer battery test. this means condition of battery relative to new, not a test which just says there should be sufficient life inthe battery to start it. the jk is as said before, most sensitive to any battery problem. if tail light is only thing running on a dead vehicle perhaps get that tail light circuit checkd as well. cheers.