Check brake pad light

[tomaszek]

Hello,

I’ve got an Audi A3 8pa 1.6 petrol 2009 and just got the check brake pad warning on my dashboard, checked the pads and discs and the pads look new? So could have this been triggered by the discs as they look quite worn?

I want to change the pads or discs by myself to save costs so not really looking to go to my mechanic.

 

[Matt268uk]

There appears to be quite a lip on the discs so maybe would benefit with some new ones. There also seems to be a lot of miles on those pads. I think I'd replace them both and that way you know your all good for the future. it's also a good idea to do it yourself as it's a straight forward job if your handy with a spanner pretty simple.

 

[samisnake]

pads look meaty. check the wiring connector for the brake pad on the passenger side.

 

[FactionOne]

Pad wear is a pretty basic system, no fancy sensing & logging or anything like that, just a circuit to ground (usually, on VAG) which when the pads wear goes open circuit and illuminates the light. As Matt says, those discs look ready for replacing; the pads aren't supposed to wear all the way to the backing, so while there does look to be meat left on them, the light might be legit (the warning generally comes on at about 25% left).

Erroneous pad wear lights aren't unheard of; generally a wiring/connector issue. I can't say for certain that this works on an 8P (though I've no reason to suspect not), but if you short the pins in the connectors the light should go out if everything else in the circuit is OK.

Rob.

 

[tomaszek]

Pad wear is a pretty basic system, no fancy sensing & logging or anything like that, just a circuit to ground (usually, on VAG) which when the pads wear goes open circuit and illuminates the light. As Matt says, those discs look ready for replacing; the pads aren't supposed to wear all the way to the backing, so while there does look to be meat left on them, the light might be legit (the warning generally comes on at about 25% left).

Erroneous pad wear lights aren't unheard of; generally a wiring/connector issue. I can't say for certain that this works on an 8P (though I've no reason to suspect not), but if you short the pins in the connectors the light should go out if everything else in the circuit is OK.

Rob.

Thanks for the reply, I’ve replaced the pads and discs on the front wheels but the light still comes on so must be something with the wiring? I’ll try what you suggested and short them out, I’m assuming you short them out while the engine is running?

Thanks

 

[Darren92]

decode the warning through the instrument cluster using vcds or similar, from memory it is in adaption, then the special function ii channel

 

[FactionOne]

Thanks for the reply, I’ve replaced the pads and discs on the front wheels but the light still comes on so must be something with the wiring? I’ll try what you suggested and short them out, I’m assuming you short them out while the engine is running?

Thanks

Whenever the light's on, really - I think it shows with just the ignition? - it should't make a difference. If I recall correctly, the plug on the car wiring is the male side, so if you disconnect them you should be able to put a flat blade screwdriver across the pins to complete the circuit. I don't know if it's the case on later models, but it always used to be one big circuit from the clocks through one side and then on to the other, so ideally you'd short both sides at the same time and work backwards from there.

If you've changed the pads and the light persists, it begins to sound like there might be an issue on the car side further back up the wiring. It probably wouldn't be the hardest thing to hunt down (I'd put a bet on it being somewhere before the wiring disappears away from the wheel arches), but another option might just be to code out the warning with VCDS (if you have it or can get to someone who does (COVID-rules compliant of course!)) as @Darren92 suggets above (I didn't know that was an option on 8P).

R