Repairs to brake wear harness

[Mark.T]

Hi
I'm just copying this quesiton from the BX FB page incase anyone here not on FB knows how the front brake pad wear indicators work. I'm thinking of replacing the long-disintegrated ends in the wheel arches, but wanted to test the remaining wiring first. Are the two wires to each side simply +ve and earth?. I recall that in the original, one of the wires seemed to feed a ruber plug with two female sockets for the wires from the pads, and there was also a wire with a ring connector that was bolted to the hub carrier.

I chekced the surviving wires in the engine bay, and measured only about 45 mV on one wire with ignition on, so tried the same on my other BX and got about 28 mV. Also, if I simply short across the two wires on either side, should the warning light come on? It didn't on either car - but I've not checked the dash bulbs yet...
Cheers

[xantia_v6]

Typically the bulb is fed with 12V , then the other side of the bulb is connected to the 4 sensor wires (one for each front pad). The sensor wires ground to the brake disk when the pads wear down.

[Mark.T]

Thanks. I'll check for voltage to and from the bulb.

[Jaba]

I know they are there and are connected but I have never seen the warning light come on even when they should.
Once I had to disconnect the cables because I was getting interference on the radio from them.
So nowadays I regard them as a very unreliable way to check for front brake pad wear.

[Mark.T]

Mine worked once... on holiday in 1994 just after I bought the car, and I then had the pads chsnged.

I've just found the warning bulb was missing from the dash... So I'm one step further on.

[rutter123]

I just check mine regularly and when they're worn I change them,
I connected mine up once with new pads and every time I turned left the warning lamp came on, they have been disconnected since, don't think I've had a bx with working wear indicators