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Randomly UNAVAILABLE ACC / FCW?

78K views 46 replies 19 participants last post by  echo7tango 
#1 ·
I searched on FCW and didn't readily see if this problem has been reported before. 12K miles on my rig, and recently got it back from the dealer for fixing the cat and P20EE.

I randomly get the EVIC message:

ACC / FCW UNAVAILABLE
WIPE FRONT RADAR SENSOR

So yeah I've cleaned it, again and again. I still get the message. Any ideas as to the cause, and to the fix?

What's also happening is, I occasionally get the bright red BRAKE! and loud beeping when nothing is there. Annoying, and alarming, no pun intended.

Well, maybe Casper the Ghost was out there on the road... :D

Thanks folks!

Roy
 
#3 ·
I've had this happen several times on long trips and it always clears itself within five minutes. The dealer checked everything out, but couldn't find any problems - the sensor is tight and seems to be adjusted properly. On my trip to Oregon and back, it seemed to occur about every 250 miles, almost acting like something was overheating and resetting when it cooled down. The regular cruise works when this happens, so I just switch to it for a few minutes and then reengage the ACC. It is irritating though.
 
#4 ·
Same problem on a 2015 with 5500k miles. The first time they said they couldn't duplicate so I have started taking pictures everytime it happens. I have enough now and am taking it in soon. My dealer is not very customer oriented. On the Ford forums Ford representatives actually monitor the forums and jump in to help resolve issues.

I have crooked steering wheel, rough shifts and this issue with the adaptive cruise. Very frustrating and I am super patient with the dealer.
 
#6 ·
Could also be happening if you drove through high snow or if smth/someone bumped into the front sensor. I had that happening last year...initially I thought it's dirty but no matter how much I cleaned it the error was coming back after 20 min of driving or so.
I did drove through high snow and carelessly bumped every possible snowbank when parking around :)
Sensor sits on a metal plate or smth and if pushed or pressed too hard need to be recalibrated. Took 5 min in my case.


Sent from my iPhone using JeepGarage
 
#7 ·
I constantly received 'ACC/FCW limited functionality' and last week, my camera module behind the windshield was replaced. Since then, it's working again. Prior to that ACC was actually working but I didn't get the 'BRAKE!'-warning messages anymore.

Tomorrow, I have an appointment regarding the crooked steering. Hopefully, this will be all for the near future..:thumbsup:
 
#8 ·
Update - my message was different ACC / FCW UNAVAILABLE
WIPE FRONT RADAR SENSOR and the dealer stated the sensor bracket was slightly bent and they relaigned the sensor. Unfortunately, I don't have it back because they are having issues with the transmission and they put me in a rental car. I hope they get the steering wheel straight too!
 
#10 ·
Jumping back in to report that the FCW / ACC was fixed and I've tested it on a few road trips. Am SO glad to have ACC working again! I was in slow-and-go Bay Area rush hour traffic and I loved its ability to track the car in front, just creeping along. It's great to have it back again, I really missed it.
 
#14 · (Edited)
Hey folks! I am new to the forum but purchased a 2014 JGC Overland 5.7L over the holidays with 64km's.

I too seem to be having a very similar issue, FCW randomly throwing false warnings, and ACC seems to be having a very difficult time differentiating between bridges/overpasses and cars. After screwing up a few times, it will throw the ACC/FCW UNAVAILABLE, WIPE RADAR SENSOR issue.

Took it in to the dealership last week (still covered under 30 day CPO warranty) and they couldn't replicate it, so I managed to put together the following video(s):

https://www.youtube.com/watch?v=8TQUcYo_vds&t=73s&index=1&list=PLeTZ55eYQz3s382p5U7ib5U3Lnw4JRrWS

(sorry for the trump news conference in the audio, had I been thinking I would have switched off CNN at the time!!)

At 00:10, "BRAKE!" FCW warning at sign underpass
At 01:01-:07, ACC stops seeing the vehicle in front (ACC set at 130km)
At 01:53, "BRAKE!" FCW warning at sign underpass
At 02:26, Mistaking bridge for Car, ACC decelerates
At 02:43, Mistaking overpass for car, ACC quickly decelerates from 120km/hr to 90 km/h, road is clear.

...immediately following this video and acting weird, I get the FCW/ACC Unavailable. This happens all the time and kills me on my daily commute (~50km each way).

Does this seem to be familiar to the types of issues you experienced? Did you receive a high number of false positives or acting up prior to the "randomly" unavailable FCW/ACC?? Did it go away once the radar was replaced?

I am taking it back in again next week - hopefully this time they will do something to fix it. If they've already checked the alignment of the radar, I assume it is most likely a faulty radar sensor?

Any chance it could be the camera behind the windshield? How do we know the difference?

Also there was a lot of really good info on how the system works here: Jeep Grand Cherokee WK2 - Forward Collision Warning Plus

Thanks in advance and I'm happy to be a new part of this community!

NM
 
#15 ·
Hey folks! I am new to the forum but purchased a 2014 JGC Overland 5.7L over the holidays with 64km's.

I too seem to be having a very similar issue, FCW randomly throwing false warnings, and ACC seems to be having a very difficult time differentiating between bridges/overpasses and cars. After screwing up a few times, it will throw the ACC/FCW UNAVAILABLE, WIPE RADAR SENSOR issue.

Took it in to the dealership last week (still covered under 30 day CPO warranty) and they couldn't replicate it, so I managed to put together the following video(s):

https://www.youtube.com/watch?v=8TQUcYo_vds&t=73s&index=1&list=PLeTZ55eYQz3s382p5U7ib5U3Lnw4JRrWS

(sorry for the trump news conference in the audio, had I been thinking I would have switched off CNN at the time!!)

At 00:10, "BRAKE!" FCW warning at sign underpass
At 01:01-:07, ACC stops seeing the vehicle in front (ACC set at 130km)
At 01:53, "BRAKE!" FCW warning at sign underpass
At 02:26, Mistaking bridge for Car, ACC decelerates
At 02:43, Mistaking overpass for car, ACC quickly decelerates from 120km/hr to 90 km/h, road is clear.

...immediately following this video and acting weird, I get the FCW/ACC Unavailable. This happens all the time and kills me on my daily commute (~50km each way).

Does this seem to be familiar to the types of issues you experienced? Did you receive a high number of false positives or acting up prior to the "randomly" unavailable FCW/ACC?? Did it go away once the radar was replaced?

I am taking it back in again next week - hopefully this time they will do something to fix it. If they've already checked the alignment of the radar, I assume it is most likely a faulty radar sensor?

Any chance it could be the camera behind the windshield? How do we know the difference?

Also there was a lot of really good info on how the system works here: Jeep Grand Cherokee WK2 - Forward Collision Warning Plus

Thanks in advance and I'm happy to be a new part of this community!

NM
This sounds similar to the problems I have had since purchasing the vehicle except that mine are very intermittent, usually occurring during a long drive (in excess of 250 miles normally). When it happens on mine, the FCW is off for about ten minutes and then can be turned back on and everything works fine for quite a while until the next time. It almost acts like something overheats and then works again after cooling down.

My dealer has not been able to find anything. I'm also wondering if something might be loose somewhere.
 
#18 ·
nmck, push for a radar replacement, try not to settle for less. They might (again, might) push back as a cost-savings measure. Stick to your guns.

Good luck, let us know how it goes. And, welcome to Jeep Garage!
 
#19 · (Edited)
Thank you echo7tango, after looking through some more threads here I think I have come across the issue. Just as a follow up, here is what my radar looks like:



Apparently there should be some plastic trim/moulding around it to keep it aligned. CRAZY that they didn't pick that up after specifically investigating my concerns. Once they fix these issues, I will be finding myself another dealer for service.

I am going to drop by today to make sure they get the part ordered so it is hopefully in stock when the car goes back in on Monday. If that part doesn't fix it, I will definitely push for the the radar replacement!
 
#21 ·
OK - So my issue was finally resolved. I had to literally hunt the tech down and tell him that the missing trim/fascia was reported as an issue on JeepGarage (He would NOT believe that it could possibly have anything to do with it), and also was able to identify that there was some up/down "play" on the sensor itself.

After I assume re-setting and installing that part, no more problems. Why the tech never bothered, within two trips on the same issue, to physically inspect the sensor for play is beyond me. Regardless, it all works now, so I'm happy.

However, my middle pillar on the sunroof is now rattling (it used to creak, they "fixed" the creak and added a rattle)... so I am just waiting until my next oil change to bring that one up again.

I still love this truck, but not sure how I feel about my first few encounters with the MOPAR service folks.
 
#23 ·
Just had mine fixed at dealer on my '17 Trailhawk. The wiring harness was completely corroded and the vehicle is fresh of the assembly line. Turns out the workers on the line didn't properly seal the plastic harness connector into the wiring harness and this caused the intermittent fail.
 
#24 ·
Mine was giving the same error too. After many cleanings of the radar sensor with no effect, I took a closer look. There are 3 screws that hold it in place, the 4th seems to be missing intentionally. I pushed on each corner that had those screws until I felt a pop, like you're popping a bone back into a joint. Now the radar sensor felt like it was firmly in place and it works fine.

I most likely messed it up by driving through huge reservoirs of water, about 2 feet deep at high speeds, probably similar to people driving through snow, with enough pressure the three bolts pop out of their joints causing the sensor to wobble, which makes it think its dirty because it can't get a signal fix.

Hope this helps.
 
#25 ·
Good to know, thanks for sharing. And welcome to Jeep Garage.

I wonder if there's a good protective element of some sort that we can use. Maybe something aftermarket to buy and install. Or maybe fabricate something. I love driving through puddles, and some of them are deep.
 
#26 · (Edited)
Hi everyone,

Just bought a 2017 Trailhawk last week, and four days into it I had the error message "ACC/FCW Limited Functionality Service Required" and "LaneSense Unavailable Service Required". Hadn't put more than 100 miles on the car and those error messages popped up. Took the car in and they ended up having to replace the camera system in the mirror. They told me this is a slightly known problem, however its only present in like 1 and 20,000 (could have been a superlative) that come off of the production line. They are hoping this fixes the problem, however they said if it doesn't they would just replace the car. I just got the car back, and will be driving it all this weekend. Very strange, I have a 2017 Summit with the same system, and bought it back in November and have not had any issues, I'm hoping this was a one off situation and the replacement land sense camera does the trick.
 
#27 ·
I've been having issues with the FCA shutting off at random times since I bought mine new. Since it never does it at the dealership, they can't get any codes and, since the shutting off only lasts about 5 to 10 minutes, I can never get it to the dealership while it's off.
 
#34 ·
The Irvine Jeep dealer today tried to tell me the sensor is pitted. Jeep choose to put the thing down closer to the pavement, instead in the center of the grille, as many other makers have done. I polished it with some plastic headlight polish, and will try again with a headlight buffer and polish if that does not work.
 
#35 ·
Did the polishing actually smooth it out? My ACC/FCW system was dropping out all the time a month ago, could hardly keep it working for more than 5 minutes. I had some front end work done at the dealer and asked them to check on the ACC/FCW too. They couldn't find any problem with it but did replace some front end parts. They claimed the front end issues may have caused a misalignment of the sensor and now that the front end is fixed that took care of the ACC problem. Oddly, it's been working perfectly since I got it back. So I think two things are possible, perhaps the alignment fixed the problem like they said... or... the fact that the temperature was 10 degrees cooler when it got it back (105 instead of 115) allowed it to work right. If it keeps working and then goes on the fritz next summer I will suspect that the problem is heat related.
 
#37 ·
I can push mine backward quite a bit (1/4 to 1/2 inch or so) which makes it seem like its in completely the wrong position.. and I can pull it forward where it feels like it's "against the stops", which seems like where it should be. But it doesn't seem like it ought to be able to move back and forth like that. But it sounds like yours does just like mine. I was thinking the adjustment/screws/mounts were broken but maybe not....
 
#39 ·
The FCW warning message pops up every day on my 2018 Renegade during my commute past some big industrial plants (Boeing being one). It sounds crazy, but since it happens so consistently in those areas during even sunny days, I wonder if there is something put out by those plants that blocks my radar? Has anyone else noticed similar occurrences?
 
#40 ·
I've never had the service required messages, but occasionally get the ACC/FCW Unavailable messages when it is raining or snowing. It tends to clear itself out after a few minutes, but when it has been snowing and cold enough for it to ice, I have had to clean the sensor before it goes away. Same thing occurs on my wife's 2019 Cherokee Overland, but not as often.

Had similar errors pop up on my Infinitis, so it is not simply a Jeep issue. Hell, those systems would not even work if the windshield wipers were on a constant speed because of the software programming, so I am thankful they remain active on Jeep despite windshield wipers being on anything but intermittent.
 
#41 ·
So I love this feature (ACC) and mine has worked perfectly, save for severe icing and the two times I did it wrong - the first time a deer took out half the bumper. But this winter I had an encounter with a chunk of truck tire at 80 mph. After popping out the damage, the lower bumper is mostly intact, nd the ACC until is still there and solidly mounted, but the bezel around the ACC unit is missing. Funny thing is, the ACC still functions, sort of. It will turn on and set itself but won't recognize vehicles in front of it. I also get the message to clean the sensor frequently. When I got a replacement bezel, my suspicion was confirmed - there's some kind of secondary lens cover that's missing. See the picture with the bezel installed:
Automotive tire Motor vehicle Automotive lighting Car Automotive design


I'm unable to find the lens as a separate part, I'd hate to have to replace the whole unit. Has anyone removed one of these and seen if it comes apart?
 
#42 ·
So I love this feature (ACC) and mine has worked perfectly, save for severe icing and the two times I did it wrong - the first time a deer took out half the bumper. But this winter I had an encounter with a chunk of truck tire at 80 mph. After popping out the damage, the lower bumper is mostly intact, nd the ACC until is still there and solidly mounted, but the bezel around the ACC unit is missing. Funny thing is, the ACC still functions, sort of. It will turn on and set itself but won't recognize vehicles in front of it. I also get the message to clean the sensor frequently. When I got a replacement bezel, my suspicion was confirmed - there's some kind of secondary lens cover that's missing. See the picture with the bezel installed:
View attachment 232095

I'm unable to find the lens as a separate part, I'd hate to have to replace the whole unit. Has anyone removed one of these and seen if it comes apart?
You can look at the below photos of the parts from my 2014. Assuming your radar "ball" is the same diameter as mine, it looks to me like the insert that goes in the fascia has too big an opening. Yours also appears to have an unneeded cutout at the top. If you can measure the size of the parts I can compare them to mine. But the "hole" in that main new piece on yours just looks way too big. I knocked mine out a couple times banging the front lower grill into the dirt and was looking online for replacements and there were many different part numbers listed and know way to figure out what the differences were. Perhaps it's the size of that "hole". My guess is you have the wrong part.

There are basically three parts in these photos. There is the radar unit with the "ball". That bare unit is what you see in the second photo down, it has the bright silver on the lower right. There is a small plastic cover to the left of the bare unit in that second photo. That snaps over the radar unit and is shown installed in the third photo. Last there is the large piece that snaps into the lower grill and fills in the gapes around the radar unit... it's shown in the fourth photo. And of course all of them installed are shown in the first photo.


232129
232130
232131
232132
 
#43 ·
Thanks! Yes it looks like I'm also missing that additional ring piece between the ball shaped lens and the plastic bezel that snaps in. I've seen those sold separately from Jeep. yours is definitely different than my 2016 though the steel part that its mounted in is a different shape. I ended up buying a used unit on Ebay that has the complete lens assembly; it appears that it clips onto the unit and covers the glass ball that's currently exposed on mine. If I can resurrect it without removing and resetting the whole thing that would be ideal.
 
#45 ·
Like bardwell and Jim say, although mine was several years ago it had to do with the front sensor. If memory serves, it was not aligned correctly. I don’t think mine was replaced, I think the dealer fixed how it was aimed.

My memory is hazy and that’s the best I’ve got for you. Wish I had more details for you. Good luck and please keep us posted.
 
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