Help needed rear parking sensors stopped working

Adam_A3_

Registered User
These were working fine yesterday. I had some work done on the car but i dont know if its related.

Had the resr wishbones replaced. They had to saw out the bolts. Sensors seemed fine after this. Then i had my alignment done on four wheels. Straight after this there is now a long high pitched beep when i first put it in reverse and then nothing. It doesnt beep if i take it out of reverse and put it back in unless i turn car off and turn it bck on. But still the sensors dont work.

Im wondering if the work i had done contributed to the sensors not working. What route do the wires take from front to back.

Any help is appreciated in diagnosing and fixing and maybe who in yorkshire can fix this for me.

Thanks
 
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Adam_A3_

Registered User
unplug each sensor to find out which may have gone 'puff'...

Thabnks for your reply. Do you think one of the sensors have stopped working? And does this in turn stop them all from working? Do i need to remove the bumper to do this?
 

SteveMcB

Registered User
On the A4, if you put it into reverse with ignition on and listen closely to each sensor you should hear a faint buzzing. All quiet means the sensor is not working. I had one dodgy sensor and the system still worked (except for a blind spot on the nearside) but when a second went it caused the same symptoms as you, don't know if this is the norm. TBH I would probably prefer the loss of one to shut down the whole thing anyway because I didn't bother getting it fixed until the second went which is probably not recommended.

Does seem a bit of a coincidence that you've just had work done, hopefully it's just a wire that's been knocked off.

On a side note I pay £200 a year for an RAC warranty and they covered replacement sensors.
 
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Adam_A3_

Registered User
On the A4, if you put it into reverse with ignition on and listen closely to each sensor you should hear a faint buzzing. All quiet means the sensor is not working. I had one dodgy sensor and the system still worked (except for a blind spot on the nearside) but when a second went it caused the same symptoms as you, don't know if this is the norm. TBH I would probably prefer the loss of one to shut down the whole thing anyway because I didn't bother getting it fixed until the second went which is probably not recommended.

Does seem a bit of a coincidence that you've just had work done, hopefully it's just a wire that's been knocked off.

On a side note I pay £200 a year for an RAC warranty and they covered replacement sensors.

Didnt know they were that expensive to replace. Do the wires feed through the inside of the car or beneath it? When i had the wishbone bushes cut off there were a lot of hot sparks. But all this was at the rear of the car. Im going to try and get under it tomorrow and see whats going on
 

Sidhu88

Registered User
PARK LIKE A REAL MAN!!









jk.... would vcds not isolate which one isn't working?
 

SteveMcB

Registered User
Mine didn't throw up any fault codes. I'm not sure how much they were to replace, keep in mind they need painted as well, I'll be keeping the warranty going though, it paid for a knackered headlight washer last year and, as well as the sensors, a replacement servotronic unit at £130 this year. Provides peace of mind against major repairs as well.

Sorry I don't know how the wires are routed.
 

Adam_A3_

Registered User
Lol. I am so lazy, have totally got used to parking with my sensors.

So i managed to find out which one it is (offside rear on the outer) as this one wasnt clicking when put in reverse. I managed to get my hand behind the bumper and fiddle with the wiring but to no avail.

My thoughts are that is it the actual sensor or is it the it some wiring that has ripped due to the sparks caused by the cutting of the bolt. Hmm. Looks like a bumper off job....

And also im interested in this RAC warranty....will look into it.
 

Adam_A3_

Registered User
Also. Any one know the part number for a parking sensor and are these universal for VAG cars?
Is there a way of replacing without having to remove the rear bumper? Thanks
 

Adam_A3_

Registered User
Bump

Anyone please?
 

leegsi

Registered User
Swap the sensor with one of the working ones.

If the fault moves its the sensor, if the fault stays in the same place its wiring.
 

omn

Registered User
These were working fine yesterday. I had some work done on the car but i dont know if its related.

Had the resr wishbones replaced. They had to saw out the bolts. Sensors seemed fine after this. Then i had my alignment done on four wheels. Straight after this there is now a long high pitched beep when i first put it in reverse and then nothing. It doesnt beep if i take it out of reverse and put it back in unless i turn car off and turn it bck on. But still the sensors dont work.

Im wondering if the work i had done contributed to the sensors not working. What route do the wires take from front to back.

Any help is appreciated in diagnosing and fixing and maybe who in yorkshire can fix this for me.

Thanks

Hi!

Were you able to solve the problem? If so, how? I came across the same issue with no apparent reason. One day, high pitch beep, and went silent.


Thank you in advance!
 
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