It is not usually faulty sensors, if you get a long tone when you select reverse, the long tone normally indicates that one or more sensors is not working. This tends to happen almost all the time after snow or severe frost. I found that cleaning the salt off the front and under the bumper sorted it out. Or you could wait till the weather improves and the rain washes away any build up of salt. Works for me every year and certainly not worth paying for new sensors which will fix the problem till the next cold spell.

 

Just got this happening on mine

 

Did the OP get his problem sorted?.

 

I have had the problem twice this year, each time after a severe frost. I just take the car to an ARC car wash (The ones that still use the rollers) and if you get the underbody sprayed & cleaned at the same time, it solves the problem almost straight away, if not wait till it all dries and all sensors will be working again. For a £2.70 car wash it is certainly cheaper than changing your sensors every year.

 

We have not had any frost and Ive looked under the back bumper and all seems dry.

 

The sensors can look clean and dry, but any salt or dirt from the roads can stick to the back of one of them and this can cause it to malfunction, it only takes a spec or two on the sensor part and it thinks they are faulty. The frost or cold weather can open up the rubber seal and let dirt in. I have had this problem for the past two years and each time Renault try to sell me new sensors but each time I clean them, they work till the next cold spell.
Does the beep come on continuously straight away or after a few seconds? And if you park about 10 inches away from an object and then select reverse, do you get any beeping tones or just the single continuous tone? I found that if you take it out of reverse when you hear the continuous tone and then put it back in reverse, you can get 3 seconds of it working properly before it goes continuous, enough time to get it parked up if you try this a couple of times.

 

Hi when you select reverse you get the short beep then a few seconds later i get the continues beep.
They have been working fine up to today.

 

Right i am getting the few seconds bleep if i park up close then it stops.
How do i take them out to clean them ?.

 

It sounds like you are getting the exact same problem I have had. During the few seconds of the initial beep and the long beep tone, the sensors are working. You can try getting someone walk past them and you will get the beep beep before you get the long tone. Usually no more than two seconds but that can be enough to park up close to something if you keep taking it out of reverse and then back into reverse, a pain, but after a good raining day with the spray from the roads, they will eventually be clean and stay working for many months to come. The sensors will be fine but one or two may have something on them such as dirt or dust. If you have cleaned the front of them, then it's probably at the back of the sensor.

 

Cheers.
Funny thing is that when i listen to them only one is ticking the other three are dead.

 

If you get someone to walk past each one, maybe you can work out which may need a good clean. I think mine have always been the two centre ones and the car wash seems to sort it out everytime.

Have had similar problems with the infra red door sensors too, had three sets of those changed under warranty, still fail after a cold day, but again a good wash and they work fine.

I'm sure the rubber seals are really cheap quality which is why I made sure this one had no sun roof. My last Scenic had two and both rubber seals went causing water to flood the foot wells.

 

This has just started on mine today, as soon as I put it into reverse I get 1 beep then a continuing beeeeeeeeeeeeeeeeeeeeeeeeeeeep.
I've just resulted to pushing the button to switch it off, if I get my jet washer out should this sort it?

Thanks

 

This has just started on mine today, as soon as I put it into reverse I get 1 beep then a continuing beeeeeeeeeeeeeeeeeeeeeeeeeeeep.
I've just resulted to pushing the button to switch it off, if I get my jet washer out should this sort it?

Thanks

worth trying and you will have to let us know.
Mines still playing up.

 

Jet wash should sort it but keep it at a distance so not too much pressure hits the sensors.

At the weekend mine were working perfect, but after leaving the car in a dusty car park, they stopped again this morning, have since washed the car and they are fine again.

 

Had to buy a new sensor in the end.
£40.80 from ebay.
Much better than Renault who wanted £90+vat.

http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=220777823420&ssPageName=STRK:MEWNX:IT

 

Hi
I had a tow hitch fitted to my 2010 scenic and when I reverse the sensors sound continuously I took the bar off and they still go full blast the local renault garage is trying to sell me a full set. this only started after they fitted the tow hitch and they said it was because of the tow ball which it obviously was not.
I have seen your other answers to cleaning the sensors but how do you get them out and are the sensors encased in the plastic bits.