Reverse sensor

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Forevertonian
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Joined: 20 Oct 2019, 23:10

Reverse sensor

Post by Forevertonian »

I've got a 57 plate C5 saloon.
The reverse sensor is not working.
Spent £20.00 on a diagnostic and nothing showed up.
So apparently it's either a fuse or the module.
Where is the fuse for the reverse sensor situated?
Everything else concerning reversing works fine.

RichardW
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Re: Reverse sensor

Post by RichardW »

Mk2 or 3? Post up the VIN then we can see exactly what's fitted

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GiveMeABreak
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Re: Reverse sensor

Post by GiveMeABreak »

It will be a MK II.

Then your diagnostic device probably isn't cutting it - only a decent bit of kit can read all the constructor ECUs.

If it is a faulty sensor, then it WILL give a fault code to a reader than can communicate with the ECU. It will tell you exactly which sensor (if any) are faulty.

A manual test: Switch ignition on, put in reverse gear, walk round to the rear and lightly place a finger over each sensor - you should feel a tingling or a slight pulsing - if it does then that sensor is working. But no substitute for a proper diagnostic. Also check in the boot area to the right of the spare wheel - the parking assistance ECU is mounted there. Check to make sure you haven't had a liquid spill onto the ECU or that it's been knocked.

There is a known issue with the rear sensors on the MK II in that water can get splashed up and run down the sensor wiring into the sensor where it stays and this will cause water damage eventually. I had to have 3 replaced because of this. I then got the techs to re-route the wiring and tidy it up so that any water would run away from the sensors.

Forevertonian
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Re: Reverse sensor

Post by Forevertonian »

Thanks everyone.
The vin number is VF7**************[VIN obfuscated, can be read by forum staff]
Last edited by RichardW on 19 Feb 2020, 15:10, edited 1 time in total.
Reason: VIN updated

RichardW
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Re: Reverse sensor

Post by RichardW »

Nothing showing against that VIN for parking sensors, so it must be an aftermarket system - you will need to trace the wires back to find the ECU/ fuse.

Forevertonian
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Re: Reverse sensor

Post by Forevertonian »

Oh blimey.
Thanks for that.

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Paul-R
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Re: Reverse sensor

Post by Paul-R »

That VIN must be slightly wrong as it hasn't been masked. Maybe the correct VIN would show something?

RichardW
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Re: Reverse sensor

Post by RichardW »

Thanks Paul should be hidden now? The last 8 digits were right, which is all I normally input, there was an extra R after the 7 which overrode the filter.

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GiveMeABreak
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Re: Reverse sensor

Post by GiveMeABreak »

Ciroen did sell their aftermarket kit - I had one fitted on a MK I C5. It was an audio unit with red bulbs that was fitted at the rear edge of the headlining. It was directly fed off the reversing light wiring, no ECU - so maybe it is one of these.

wheeler
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Re: Reverse sensor

Post by wheeler »

First things first, are the reverse lights working?

Hell Razor5543
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Re: Reverse sensor

Post by Hell Razor5543 »

wheeler wrote:
19 Feb 2020, 17:07
First things first, are the reverse lights working?
And do you hear a 'bong' noise when you put her into reverse? If the lights don't work and no 'bong' it is probable the reversing switch has failed. This would then have the knock on in the sensors not working either.

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myglaren
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Re: Reverse sensor

Post by myglaren »

My bong is only intermittent :(