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M1tchy
08-04-2018, 07:09 PM
I knew my front pads were low and recently the warning light came on. I booked the car into my local Indy who changed the pads and while they were at it, I had the discs done too. All back together and the warning light remains on. No VCDS fault codes, the brake fluid is at the right level and I checked their work and itís all ok (warning wire connected).

They said on the A6s they have recently seen an issue with the with the wiring harness being corroded and failing. I find this odd as the light cane on at the correct time as the wire wire through.

Anyone know what the issue may be?


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Crasher
08-04-2018, 07:18 PM
It is very easy to route the wire incorrectly and have it cut or worn though by the rotating parts. The pad warning system is not liked to the diagnostics as it is a simple closed circuit checker.

M1tchy
08-04-2018, 07:43 PM
Iíll have another check. All looked good to me when I took the wheels off yesterday when putting the summer set back on.

Just strange it appeared with the genuine low pads but now not disappeared


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A6S
08-04-2018, 09:13 PM
Did they replace the sensor? Normally once the sensor has been triggered itís pretty much buggered. Sensors are fairly cheap and some pads comes with them.

M1tchy
08-04-2018, 09:49 PM
Yeah itís a brand new looking sensor. Suppose I could multimeter test it?


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A6S
08-04-2018, 09:58 PM
Some Audiís/vw were bad for corrosion in the plugs/terminals. Might need a squirt of wd40 or something to clean it up.

JayNana
08-04-2018, 10:38 PM
I knew my front pads were low and recently the warning light came on. I booked the car into my local Indy who changed the pads and while they were at it, I had the discs done too. All back together and the warning light remains on. No VCDS fault codes, the brake fluid is at the right level and I checked their work and itís all ok (warning wire connected).

They said on the A6s they have recently seen an issue with the with the wiring harness being corroded and failing. I find this odd as the light cane on at the correct time as the wire wire through.

Anyone know what the issue may be?


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Guessing u ruled out the obvious next? - the rear brakes also have a sensor


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shabazmo
09-04-2018, 08:49 AM
When the sensor shorts and illuminates the warning light, is it because it is in contact with the disc or is it because the sensor wears as a result of rubbing against the disc and is therefore closed circuit.

M1tchy
09-04-2018, 09:42 AM
Yeah itís not the rears, I had them done 6 months ago. Iíll check it with a multimeter later and see how the contacts look.


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Crasher
09-04-2018, 10:20 AM
When the sensor shorts and illuminates the warning light, is it because it is in contact with the disc or is it because the sensor wears as a result of rubbing against the disc and is therefore closed circuit.

It is a closed circuit until the sensor wears through and breaks the circuit which is why a broken wire brings the light on.

KevTrem
09-04-2018, 03:04 PM
When Audi did my rears last year they mentioned that the fronts where low and needed changing, I declined. They said that the harness had corrosion on the plugs. When I changed the pads myself I found they hadn't plugged in the sensor correctly leaving the light on. As Crasher says the sensor is just a loop of wire that gets worn through, once worn through it puts the warning on, its not complicated.
The harness that it plugs into is apparently prime for water tracking back up it. They do a repair harness for about £120 a side plus labour for fitting. But that was early last year I got the quote.

M1tchy
09-04-2018, 07:24 PM
Thanks Kev, Iíll have a look into it if it stops raining tomorrow. Iím overseas again for 3 weeks from Thursday so may be a job for when Iím back.

It seemed to be plugged up correctly


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