LEFT AND FORWARD COLLISION WARNINGS SUDDENLY very active

[Hebden]

Today, for the first time have had multiple red collision and P warnings on the left and front. Having read through the manual these are definitely parking sensor warnings. Nothing really to cause this.  Is it likely to be a camera or sensor fault or is there a recall of some kind out? Also wondering if anything has accidentally been adjusted or reset.  We usually set off with the forward white line crossing turned off.  Appreciate advice.

[Nicksey]

An oddity. There is a junction I regularly use, a traffic lighted crossroads at a busy junction. This particular route for me involves a right turn, generally using a filtered light at some point. If I get to the lights at the front of the queue and am at the red, the front sensors go barmy! There is a pedestrian protection barrier to my right approx 3' from my side, nothing in front or to my left.. yet the sensor goes red and starts beeping.
Only at this junction do I experience it, no other.

[Lord Voltermore]

An oddity. There is a junction I regularly use, a traffic lighted crossroads at a busy junction. This particular route for me involves a right turn, generally using a filtered light at some point. If I get to the lights at the front of the queue and am at the red, the front sensors go barmy! There is a pedestrian protection barrier to my right approx 3' from my side, nothing in front or to my left.. yet the sensor goes red and starts beeping.
Only at this junction do I experience it, no other.

Nicksey. I think your case may be because those traffic lights uses LED bulbs.  I think led's actually pulsate at a set frequency which the human brain interprets as a constant light,  but dashcams sometimes record them as flashing lights  because it interferes with their own sampling frequency.  I might be wrong but I vaguely recall this could also affect the signals sent out and received by parking sensors. Or if its not the led's maybe the traffic lights communicate with each other using wireless signals  . Parking sensors can sometimes be confused by signals from other cars. 

Hebden  .Have you checked the sensor is clean.  I get bug splats of various  colours and hues from white to black  . If its a close  match to your car colour it may not be obvious.

[His_name_is_robertpaulson]

I have this problem in my mk3 with collision warning and parking sensors when stopped behind Audis,  BMW's and Teslas.

[Kremmen]

There have also been very similar reports with the latest 11G Civic

When those with dashcams checked it was with a 10G Civic in front when stationary at lights / junctions

[Hebden]

Thank you all for your replies.  As it continued today - including when waiting at a roundabout - called into the local Honda dealer in Clitheroe who was very helpful - especially as we lived here!   We waited whilst it was investigated and then confirmed that the Parking sensor, probably forward but could be back was defective now.  Possibly due to heavy rain.  Hmm there's been much more rain previously.  It appeared to be a known issue.  Where one sensor fails it then triggers the others to alert progressively - so it could even be the rear ones.  Will be replaced under warranty next week.

[coldstart]

...
We waited whilst it was investigated and then confirmed that the Parking sensor, probably forward but could be back was defective now.  Possibly due to heavy rain.
...

Do you happen to clean your car with a high pressure washer?

I've checked the Honda manual but found nothing special, whereas Volkswagen expressly state that the parking sensors should be cleaned only shortly while keeping "enough" distance, as they might be damaged otherwise.

[Hebden]

Not normally.  Often handwashed.  Occasional garage jet wash.
 

[coldstart]

Not normally.  Often handwashed.  Occasional garage jet wash.

okay, then you are on the "clear" on this one (I'm just not willing to buy the "heavy rain" part though)