Brakes/ABS Light Question

[Duck]

Car started making an erratic "clicking" noise under my feet while driving from time to time. Sounds like a relay closing and opening, mostly noticeable when letting off the accelerator (coasting/overrunning) and never occurs while at a stop. It's almost like that little "Brake check" routine that the car does a few seconds after moving off when you first turn it on, but a bit more pronounced (maybe because it happens when I'm not expecting to hear that little check routine). After a few minutes of driving, the Orange Triangle and (ABS) lights come on...

What is under the driver's feet from a mechanical standpoint - is that the brake booster? Is that powered by an electric motor or something? Could a tooth missing on the tacho wheel that the little prox switch picks up for ABS be missing and that would cause it to fritz out? (if that were the case though, I suppose the triangle would flash like it does when ABS/ESP kick in)...

-Iain

Edited September 13, 2015 by Duck

[tolsen]

Brake booster is vacuum operated. Perhaps brake light switch is faulty.

[Duck]

I don't think it's the brake switch; the brake relay is over on the right-hand (passenger) footwell, and it's a very different kind of click (much louder, harder).

[smart142]

I'm with Tolsen, I would think the brake light switch is causing the problem.

[tolsen]

ESP unit is under your feet. Let's pray that one his not on its last leg.

[Francesco]

That would suck. Only solution to that is a donor car; dealer price is ludicrous. RRP for the lateral-G sensor alone is $450. The ESP unit is over $2000.

[Duck]

I'm with Tolsen, I would think the brake light switch is causing the problem.

I don't think it's the brake switch; the brake relay is over on the right-hand (passenger) footwell, and it's a very different kind of click (much louder, harder).

[smart142]

A star computer could help make the correct diagnosis.