Audi A4 - Brake warning light on startup

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Fri 14 Aug 2015 12:40
Audi A4 - Brake warning light on startup - Steveieb
My 2003 A4tdi has recently started showing a brake warning light on strt up. This goes out when I press the brake peel and dons,t come on again until the next time the car has been left overnight.

I initially thought it was down to the car being left on a slope but this has now been dis proved.

There is some mention on the forums of the fault being down to a poor battery.

The last time it happened I cured it by topping up the fluid. But the fluid is up to th filer level as I find it impossible to see the level through the master cylinder casing.

Grateful your help.
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Fri 14 Aug 2015 18:58
Audi A4 - Brake warning light on startup - elekie&a/c doctor

Nothing to do with a low battery.Could be a problem with one of the pad sensor wires damaged.Not uncommon on these.

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Fri 14 Aug 2015 20:47
Audi A4 - Brake warning light on startup - Steveieb

Thanks elekie.

The pads are fairly worn to about 1/4 inch. Could the problem be the wear sensor.

Strange thing the warning comes on before I try to start the car and goes out when I press the brake after start up

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