From time to time I get this error message when it rains, maybe once or twice a year. Recently it rained and the message came up.

Problem is, now after a few minutes of driving EVERY single time, I get the message and of course am unable to set the cruise, even though it is hot, dry and sunny. I can set the cruise and it works up until the point it errors out.

Ideas?

EDIT: I'd like to add this has been going for 7 days, every day. Tried an experiment. Started the car, drove around for less than 5 minutes, then parked, left engine on for 10 minutes. No error, then began driving again and within the usual 5 minutes up pops the error. cruise control then stops working and forward alert also stops working, however park distance sensors still work. hmmmm......

 

bump...

 

Sorry I missed this the first time jahummer. The ACC Sensor Blocked message can happen for a few reasons. You have figured out the rain part, snow and slush [not your problem] can do it also. Mounting things on the front can cause issues, and some aftermarket grills can interfere with it. It can also happen in wide open areas the have little or no "stuff" along the side of your travel lane, or no oncoming traffic for long periods. What it amounts to is the radar unit isn't seeing the bounce-back of the radar, for whatever reason. The radar constantly scans side to side so horizontal alignment is not really critical, but vertical alignment IS. It might be smart for you to make sure [with the car LEVEL] that the radar unit face is perfectly perpendicular to the road surface. If it points high or low, it may not be seeing the stuff at the sides correctly. Pointed up, the radar just fires of into space, for instance; pointed down, it just glances off the road surface and into space again. If you find it needed to be leveled, it would be smart to have a dealer put it in alignment mode [that requires IDS/SDD] so it can calibrate itself again.

Good luck!

 

Hi Steve,

Thanks for the response. That gives me some ideas, particularly for a period of time I drove without the tow covers on. The problem started when I replaced the covers. Perhaps the sensor recalibrated itself? I am assuming it is the rectangular box behind the driver's side cover?

 

It is behind the LH cover. That really shouldn't have been a problem unless you got the primered versions and had them painted. The correct covers for that car should have been ready to snap in, already finished. Paint with metallic or semi-metallic pigments can be a problem.

Cheers,

 

That may very well be the issue. Anyway to recalibrate to compensate for paint?

 

Personally, I would suggest popping out the LH cover and running a while to make absolutely sure the ACC doesn't give you anymore trouble first. If you get no more 'blocked' messages we can blame it on the cover. That would also negate the recalibration being necessary. Then you can deal with the cover.

OOPS! I missed your point......no, there is no calibration the will compensate for any finish that is possibly interfering with the radar.

Cheers,

 

Sorry for so long to get back to this. I did indeed verify with the cover removed, the ACC and forward alert work without failure. I spoke with Jaguar about this and they had no idea that chrome could cause this problem.

Guess I am going to be selling these nicely chromed parts. Anyone without the ACC option want to update their bumper? It looks very nice!

 

Superb, juhummer!! Thanks for getting back to us. We like it when the fix works out to be that simple.

This just serves as a fine example of what we techs ALWAYS have to be on the lookout for. Not only do we have to worry about outright failures, but also for any other possible complication to the issue, intended OR unintended. You did good, you kept an open mind and listened to suggestions. Look what it got you.......

Keep on JagIN!

Cheers,

 

I installed a toll-road sensor on the front license plate of my car. Could this cause the Forward Alert to switch off as indicated on my display panel? I never made the connection and thought I accidentally switched the Forward Alert off but couldn't find anything in the manual to help me turn it back on again. Now I am thinking it was this toll-road sensor frame I put on. Anyone know if it is causing the forward alert sensor to be off? I guess I could take it off but before I do that I wanted to know.

 

I'd say there is a very good possibility. Take it off and report back.

 

It wasn't the toll-road sensor...I took it off but car still randomly displays the error message and even more disturbingly, when this happens the engine shuts off within a few seconds and the car is dead...this has happened several times to me while I was driving at speeds up to 60 MPH. To get it restarted I finally figured out you have to turn ignition off, take the key OUT and then put it back in and restart. Overall, this had happened about 5-6 times in the 4 yrs we have had the car. Next time it does it, I will take it in to get looked at.