brake warning light

[sh4m41l]

hi all,

when i start my audi a4 avant everyrthing is fine, but as soon as i drive off the brake warning light comes on

any ideas??

sometimes i might turn the ignition on and the brake warning light comes straight on before firig the engine up

[yaman]

Check your brake-fluid level

Regards
Jim

[a8 tech]

When the light comes on press the check button, this will show low fluid.
This is not the fault
The fault is caused buy battery voltage drop/spiking when cranking
Search the forum I posted the modification to remove the dash circuit from X relief cranking
You must also ensure battery is in good order
The mod involves installing a relay to the dash circuit.
Attachment 9881
Point No.
Assignment on the relay
Assignment on the relay plate (Part No.: 443,937,527)
Vehicle connection point
electric function

1
terminal 86
pin 4
near light switch, pin 2
terminal 75

2
terminal 85
pin 6
right A pillar earth point
earth

3
terminal 87
pin 8
yellow/blue cable in the wiring loom to the socket box of the right A pillar (T10c / pin 10)
signal cable of brake fluid switch, engine compartment side

4
terminal 30
pin 2
right socket box A pillar, plug T10c pin 10 (yellow/blue cable)
signal cable for brake fluid switch, dash insert side



Quantity
Part number
Designation

1
1H5.951.253
relay number 143

1
443,937,527
9 pin relay plate

2
000.979.114
Single wire of flat push-on contact with lug 6.3

2
000.979.135
Single wire of flat contact with lug 4.8

1
000.979.137
Single wire with connector A6.0

1
111.971.939.B
blue crimp connector; cross section 1.5 - 2.5mm2

3
111.971.940.A
red crimp connector; cross section 0.5 - 1mm2