Reverse parking system problem.

[paullus]

Hi.
My S70 has factory fitted reversing sensors fitted in the rear bumper.
I have just had the rear bumper resprayed and now the system doesn't work. I engage reverse and get the single long tone which seems longer than usual but then nothing at all else happens. The system is no longer detecting anything behind the car.
Any ideas please?
BTW the guy who did the respray did not remove the sensors from the bumper when he took it off the car.

Has anyone successfully replaced a genuine system with an aftermarket one?

Cheers.

[Cubes]

Silly, but obvious question, has he painted over the sensors?

[volvokid]

This is exactly the same as me, my bumper was painted and they haven't worked since, I get the single tone but nothing after it.
Cubes my sensors where repainted too

[Cubes]

Would it not be worth carefully removing the paint from the sensors? My thinking being that the paint might create a block, rebounding the signal straight back just as it would if you'd reversed right upto something, or put your hand over it.

[volvokid]

But the sensor doesn't register anything there, when you engage reverse you get av solid beep for about 5 seconds , keep the car in reverse and put an object beside a sensor and it won't beep :-(

[wacky racer]

We do alot of work on parking sensors at work ( VW bodyshop)
If the bumper had been removed then it sounds like the loom/ plugs for the sensors have not been plugged in.
One continuous tone when you FIRST put the car in reverse normaly indicates a fault in the system.
Too much paint build up on the sensors usually means the sensors are picking up the paint and the reversing tone stays on CONSTANT.
I would Check all connections to sensors and loom.

[volvokid]

I had a quick look under my car and there is no easy access into the back of the sensor

[paullus]

The thing is the sensors were originally painted and I cleaned them off before it went in for the resparay. They worked when originally painted and after I cleaned them.
I'm wondering if they haven't been connected up properly but I think it means removing the bumper again to check.
Cheers.

[paullus]

We do alot of work on parking sensors at work ( VW bodyshop)
If the bumper had been removed then it sounds like the loom/ plugs for the sensors have not been plugged in.
One continuous tone when you FIRST put the car in reverse normaly indicates a fault in the system.
Too much paint build up on the sensors usually means the sensors are picking up the paint and the reversing tone stays on CONSTANT.
I would Check all connections to sensors and loom.

Hi.
I get the long tone when I put it into reverse and then nothing.
I'll have to check the wiring.
Cheers.

[volvokid]

The thing is the sensors were originally painted and I cleaned them off before it went in for the resparay. They worked when originally painted and after I cleaned them.
I'm wondering if they haven't been connected up properly but I think it means removing the bumper again to check.
Cheers.

Let me know how you get on :-)

[wacky racer]

So, any luck with the sensors?

[foammanmark]

Would it not be worth carefully removing the paint from the sensors? My thinking being that the paint might create a block, rebounding the signal straight back just as it would if you'd reversed right upto something, or put your hand over it.

Even excessive muck on the sensors will cause them not to function properly, never mind a coat of paint. I have to clean the sensors on my V70 when the back of the car is really mucky, or else I get the single tone.

[Cubes]

I dealt with a crash last night. It was a low speed impact but the rear bumper dressing had been moved off its mount, disturbing one of the sensors. When I went to move the car it gave the exact same symptom as yours. So I'm thinking maybe just one of the sensors has been damaged or not reconnected properly. So aswell as checking the loom connector (if indeed there is one) it would be worth checking the wiring to each individual sensor.

[paullus]

No update at the moment. I'm planning to remove the bumper next week sometime. I've got the loan of a spare module and a sensor to try too.
Cheers.

[paullus]

All working again. I bought a complete kit from Mike at FRF-Volvo. I have to say I have nothing but praise for both Rufe (Simon) and Mike at FRF. They are both incredibly helpful.
The complete kit worked out significantly cheaper than buying the major components separately. And what a kit it is (Made in Russia too!) It includes every single loom, screw, wiring connector, mounting kit, black sticky stuff for securing wires, template, pop rivets for the inner wing etc etc and around ten full sets of instructions to install the whole thing from scratch. Anyway I started off with the simple job of replacing the module first and then the on/off switch in the hope that that would cure the problem but no the bumper had to come off. A bit of a struggle as the O/S mounting bolt took a lot of persuasion to come undone. Once removed I got my long suffering better half to lay some dust sheets down in the living room. I wanted to protect the new paint as best as possible. Getting at the sensors is a major P.I.T.A!! The pretty bit that you see contains some very strong polystyrene and a substantial alloy cross member. This is to absorb impacts and what makes up Volvo's legendary safety. This all had to come out to expose the sensors. I had to engage the assistance of a wooden drift, rubber mallet, wife and moody nineteen year old son to achieve this.
When stripped down the plastic outer bumper is as rigid as a banana skin!
Popping the sensors out is simple as is putting the new ones in.
A quick point here. The instructions explicitly state that the new sensors must be painted for them to function correctly. It does warn about paint being too thick causing malfunction. I had very carefully primed and painted the sensors with light coats prior to installing them.
Once the sensors were in I, sorry WE rebuilt the bumper (wife just checked what I was writing) and it was ready to refit. I laid it behind the car before mounting it and connected the loom to the sensor module. I then turned on the ignition and engaged reverse and heard BEEP, not beeeeeeeeeeeep. I got out and walked behind the bumper, beep beep beep etc. It works! Refitted the bumper, job done!
The only downside is that I am left with a box full of bits from the comprehensive kit and non-faulty parts that I changed.

[Cubes]

Glad you got it sorted.