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-   -   Intermittent FCW light (http://www.jeepgarage.org/f73/intermittent-fcw-light-29638.html)

lkvanbelle 10-12-2011 05:41 PM

Intermittent FCW light
 
3 Attachment(s)
This past weekend I took my 8K mile, 4 payments made overland summit out to the Mounds in Mt. Morris Michigan to get a little dirty, which I did, got good and dirty. Only apparent damage was I lost the chrome strip on the leading edge of the front air-dam.

Not the problem.

Driving home. use the ACC like usual, it turns itself off after i get the clean forward sensor warning. also the FCW light begins to come on sporadically random BRAKE! warnings and the ACC repeated turns itself off and becomes available. ok. So i take it the quarter car wash and get the major junks off, then run through the regular car wash. sensor is clean, however.....

Same condition, intermittent ACC shutoff, FCW warnings and BRAKE! warnings.

Any one else had this happen?


2011 rugged brown pearl. Overland Summit 5.7 all the toys, no longer a mall crawler

12167jeep 10-12-2011 08:32 PM

Re: Intermittent FCW light
 
Maybe you scared the hell out of it and it doesnt want you driving it anymore. Try the good old disconnect the neg battery cable, might reset it. I work with some expensive machine and killing the power seems to be the fix 99% of the time.

coryhakala 10-12-2011 08:34 PM

Re: Intermittent FCW light
 
I had the same conditions you are talking about, after I hit a coyote!
I found my problem was that the sensor had "poped" out of it's mount all I did was push down on the sensor and it snapped back into place. I haven't had any more problems with it. Good Luck

schmieg 09-16-2014 03:59 PM

Re: Intermittent FCW light
 
I hate resurrecting an old thread, but I had this problem about every 250 miles on my recent trip. The ACC would shut off and the FCW light would come on for about five minutes, then go off and everything would be fine for another 250 miles. Nothing seems loose and the sensors were clean. Has anyone else been having this?

f1anatic 09-17-2014 06:53 AM

Re: Intermittent FCW light
 
Been there done that. My wife *may* have hit some snowbank when parking which misaligned the sensor. Your sensor needs to be re-calibrated and re-aligned and it will likely take a few trips to the dealer until they can diagnose it.

What they do is an elimination process which is ineffective because here we already know (due to institutional knowledge) what the problem is. The dealership is likely to tell you there are no codes, let's keep it under observation, they might suggest updating the firmware, progressing to you leaving the car. Until a tech can experience it, you will not really make any progress. Try to safely videotape it if it is reproducible in certain conditions, showing (both the dashboard and the space in front of the car). Safely means you don't videotape yourself - use a GoPro or a passenger to videotape while you pay attention to the road.

The sensor is very expensive and dealerships will go to utmost lengths to avoid ordering a new part for you. And no, visually you cannot tell whether it is misaligned or not. The sensor cover can be replaced if cracked or scratched but you most likely still require re-calibration and re-alignment.

nicjak 09-17-2014 08:20 PM

Re: Intermittent FCW light
 
i have been chasing same problems, have since found an earthwire ribbon broken from the body to the block behind the alternator the ribbon actually presses onto a button. also just found main earthwire alternator too body loose. keep in mind this car had a new motor installed. im told earthing problems are a main cause of faults on these models.

schmieg 09-17-2014 08:41 PM

Re: Intermittent FCW light
 
Quote:

Originally Posted by nicjak (Post 1088756)
i have been chasing same problems, have since found an earthwire ribbon broken from the body to the block behind the alternator the ribbon actually presses onto a button. also just found main earthwire alternator too body loose. keep in mind this car had a new motor installed. im told earthing problems are a main cause of faults on these models.

Good information. I will check that out. The problem is that I have to take a long trip to find out if something works.

nicjak 09-18-2014 01:24 AM

Re: Intermittent FCW light
 
2 Attachment(s)
mate heres the troublesome earths they caused all the same faults you have mentioned,

schmieg 09-24-2014 11:14 PM

Re: Intermittent FCW light
 
For the last two days, the Overland has been in the shop where they have been trying to track this problem down. They couldn't find any loose grounds and they recalibrated the sensor, but they couldn't duplicate the problem (not surprising since it was so intermittent to begin with). The service manager told me to bring it back if it happens again. He notified Chrysler about it and I told him that I wasn't alone - that others in this forum had reported the same problem.

It was acting almost as if something had overheated, shutting off for about five minutes and then turning itself back on. I usually got the message that the sensor need to be cleaned, even after I had just cleaned it, but once, I got the needs service message. Unfortunately, I was driving the Bear Tooth Pass north of Yellowstone when that one came on and I didn't have my code scanner with me on the trip (think I'll throw it in next time). I've also gotten the false BRAKE!! warning a couple of times, but, luckily, no application of the brakes.

I'm driving to Wapakoneta and back tomorrow, so I'll see if it happens and possible throws a code then.

At least the dealer believes me and is willing to look for the problem.


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