Front parking sensors giving false proximity warnings.

[Paul@FreewaySOM]

I've got a BlueHDi 120 S&S Prestige that I use as a driving school car. This is my first DS3 that has front parking sensors fitted, the previous 2 only had the rear ones. Recently I've noticed that the front sensors start to show a warning that there is imminent risk of hitting something directly in front of us, despite the road being clear. Sometimes, approaching a downhill junction to meet a level road, the sensors will again give a false positive. At first I was baffled, cleaning the sensors in case there was dirt or something on them had no success. Then the other day something had me wondering. Last week, whilst we were enjoying the warm dry weather, the sensors seemed to be behaving, this week as the weather turned wetter, the problem started up again. Thinking back, it would appear that possibly the rain is having some effect on the sensitivity of these sensors.

I had issue the other day with an examiner bending my ear because the front sensors were giving a false warning whilst the candidate was doing their turn in the road manoeuvre, he said there was nothing within 6ft of them. Since then I've been made aware that at least two other instructors are having similar issues with them. One via conversation with another examiner, and a colleague I was talking to this morning. He's turned his sensors off to stop the distraction getting to his drivers, and was suggesting that maybe the sensors are positioned too low to deal with the wind effect and rain on the new facelift version, or possibly angled wrong. Of course, in order to turn the front sensors off it means deactivating the rear ones as well.

Has anyone else had problems with these factory fitted front sensors, and if so, has the weather been wet at the time? I've spoken to my local dealer's service department who is going to query with Citroen technical whether they are aware of any issue, the service person said they themselves weren't. From thinking it was just a fault with my car, I'm now thinking this might be more widespread.

[Bigfeet]

Our boss runs a DS3 with the front sensors and never reported any issue, they do pick up a low kerb if the nose is angled down but never picking anything up that wasn't there.

When the alert comes on what stage is it at, one green, two green or red?

[Paul@FreewaySOM]

That's the type of thing I'd expect them to pick up to be honest, and when they do work properly, they start at one green bar. However, when this issue arises, the display screen shows red all around the front of the car.

Off to next lesson so apologies if I don't get back on here until later this evening, but thanks for your quick reply.

[Bigfeet]

Okay if the sensors are going straight to red then it would hint that one of the sensors is failing. I would suggest having them checked and replaced by your Citroen/DS dealer.

[BenS]

Rain can get trapped behind them if the seal is damaged, does the problem disappear if weather has been dry for a while?

[Bill the Badger]

We occasionally get the same problem with our Land Rover when it has been raining, somyou may be getting the same.

[Paul@FreewaySOM]

Got car booked in with local dealer for examination next Thursday. Been asking on an instructors group and have 3 more replied with similar issue so be interesting to see how Citroen respond. One instructor has had one of the sensors replaced but has since turned the whole system off.

Regarding the seal, it does appear to be when the weather has been wet, especially heavy rain. Today it's been more drizzle than like what we had a couple of days ago, we had one brief false warning this afternoon. Is the seal behind the bodywork? Wondering if a thin bead of clear sealant on the outside would stop any ingress.

[Hyperkev]

My drive dips a little as it meets the road and mine goes off now and again when I pull away.

[Gal]

I had the same problem especially in the wet. Even the boss of the local delaer has had this happen. They took my Performnace in and did some tests which showed nothing. They advised the D'S technical department who have never replied to the query. Basically it's a feature shall we call it. No fix is imminent.

[BenS]

^^^ A feature to make sure you don't crash into those pesky raindrops, I like it

[Paul@FreewaySOM]

Brief update:
Car went in to the dealership yesterday for investigation and the initial tests found no fault. Then just as they thought they had done, it gave a false positive in the workshop. Not rained here for a good few days now but had still briefly faulted Tuesday evening 3 times. Dealer is ordering new sensors to be fitted as and when I can find time. I mentioned the advice about the seals being damaged so they are going to look at that when they do the replacement.

[Ryan.A]

Brief update:
Car went in to the dealership yesterday for investigation and the initial tests found no fault. Then just as they thought they had done, it gave a false positive in the workshop. Not rained here for a good few days now but had still briefly faulted Tuesday evening 3 times. Dealer is ordering new sensors to be fitted as and when I can find time. I mentioned the advice about the seals being damaged so they are going to look at that when they do the replacement.

Hi Paul - Same here been a driving instructor for nearly 20 yeas, and have been having the same problem for the nearly 3 years now with my DS DS3 Ultra Prestige, changed sensors, went in for testing etc. Have you found out the problem? Also as an ex mechanic, have had a good look around, but don't want to touch anything as still under warranty, but I have noticed if you can mange to get your finger through the grill and move the wire a bit, it does stop for a while. Please let me know....Thank you