Brake pad warning light
My 2001 Audi RS4’S brake pad wear warning light is permanently on because the connectors on the car side of the pad wear indicators have broken over the years and I have never felt the need to repair them. Is this now a MOT failure?
I do, of course, check the pads regularly, but I’d like to do a permanent repair. I assume I will have to solder in new connectors to the car circuit for the pads to connect into – are these connectors standard and easily available or are they dealer-only items? Can you recommend a supplier and does it matter which way round the two wires are connected? If so, how can I tell which way round to solder them to the new connector?
Would it be acceptable, as a quick fix, to switch off the warning light? Is this as simple as connecting the contacts together at each wheel to simulate a circuit in the pads? If not, what will turn out the light pending a permanent solution?
Pat Brooks
According to the latest MOT instructions, the illumination of the brake pad warning light is a Major fault and this will be an automatic MOT fail.
The brake pad warning light circuit is quite a simple circuit and is purely a loop. The circuit will illuminate the light if the loop is broken or if the circuit touches earth. This means that when the brake disc contacts the wire it will begin to show up on the dash. When the wear is so bad that the wire is cut through by the brake disc, the light will remain on.
As the circuit is a loop, it doesn’t matter which way round the wires are connected. As you are competent on working on your own vehicle, it may be easier to simply cut the plug from the warning wire on the new pads and solder the connections together. This will mean that, when you replace the brake pads again, you will have to repeat the process but it will save the cost of a wiring loom, which you would need to buy from Audi.
Another alternative would be to visit a breakers yard and cut the required sockets from another Audi. There are a couple of variations to the plugs, so ensure you have the correct type.
If the brake pads are in good condition, the light can be extinguished as a quick fix by joining together the two wires from the loom together – this will complete the circuit and extinguish the light. It will, of course, leave you without a low-pad warning light.