Hi Guys,

I had a track outing last weekend that didn't end up so well. I have experienced during a spinout that the VSA Caution and ABS light all turn on until you turn off the ignition and cycle it and restart the engine, but this was not the case. I always turn VSA off when I get on track and randomly during the middle of my track session the abs, vsa, caution and ebrake light all turn on for no reason. I don't even have an ebrake installed anymore since I have the stoptech bbk in the rear that eliminates the ebrake. This eventually lead to me locking up the tires down the front straight heading straight into the tire barrier and luckily I was not injured. The passenger airbag deployed and the front end needs some cosmetic repairs.

My question is what could have caused this to turn on? I made sure that my brake fluid level was topped off before I left. I've read that a faulty speed sensor, or a faulty vsa module could be the problem but this has never happened to me before. I have no DTC lights or any error codes stored and I'm at a loss of words. Could anyone chime in with their experience with this and how they solved the problem? I did search before posting this topic, but most just mentioned a faulty speed sensor or low brake fluid or a stuck brake master cylinder. I'm trying to derive the sole cause of the problem so that this doesn't happen again, because going down that front straight and having the tires locked up is not a fun time, for my physical well being nor my wallet.

Thanks guys!

 

Did the brakes lock up quicker than normal or do you typically rely on ABS instead of threshold braking?

 

Almost certainly a wheel speed sensor. Chances are that the heat from the rotors caused them to overheat and fail. Once a wheelspeed has failed ABS/VDC will shut off.

 

^ should store a code though if there is a wss problem. I would lean more towards a loose power or ground issue. if the module looses power it would lose any codes or data. on a power cycle it would do a regular bulb check though... maybe this is what you're seeing?

 

I had brake/vsa lights turning on intermittently on the track as well. It turns out, when I took out the knuckle for bearing replacement, I didn't tighten the abs sensor down completely. The 1~2 mm play causes the computer to turn off ABS.

 

thanks guys. i'll check the car for possible solutions.