Rooster'sTL

So my brake lights haven't been lighting up very bright, sort of like they are only half on or something. I had a feeling it was the switch under the dash, because if i pushed the petal to the side a little bit they would work properly. I got under the dash and see one switch attached to the brake. I pull it out mess around with it a little and put it back in. My brake lights work! Great problem solved.

I head off to work this morning and my TSA light is on. I think it is a little weird, hit the button...nothing happens. As i pull up to a red light i take my foot off the gas and my car SLOWS way down. i take off from the light and it feels like i'm going up the side of a mountain. I figure BAD NEWS, and turn around and drive home...I have only gotten about a block. by the time i get back to my house the brakes are smoking like no tomorrow.

Why would the brake light switch do that? Isn't it independent of the actaul brake system?

Have a totally destoried my brakes? I figure the pads and rotors are toast, but how can i tell if the calipers are bad too? Or if anything else needs to be replaced?

Any suggestions would be appriciated.

Rooster'sTL

By the way it is an '04 Auto.

Majofo

wtf? damn rooster.. that sucks. Post pics up if you can.. I can't imagine why this would occur. I am under the assumption modern brakes are still mechanically controlled. What did you do exactly when you were messing with the brake switch? I'd check with the play of the brake pedal and see if something is exerting any pressure.

Your brakes and pads might be okay but pics to be sure.. check for warping when they cool down. Your calipers are probably fine.

Majofo

ahh crap.. 5 min limit.. you say your TSA (you mean VSA) light came on.. grab the codes from the car. I suspect your brake light position sensor is not connected or is loose.. Make sure that sucker is on. You might need to replace it. Make sure all the components are as they should be (lock pin / bolts).. The brake pedal position sensors feeds to the fcan and might definitely be the reason for the brakes to engage. Also.. were all your brakes smoking? It could be a stuck piston which would require a rebuild but if you say it was fine and then it acted up after messing around with it.. I'd say bpps.

1fstTL

iTrader: (1)

lol when i tried to take out my dad vette last week the rear brakes were stickin and A LOT of smoke was commin out, turnd out to be a bad master cylnder

Rooster'sTL

Everything under the dash is connected correctly...lock, pin, bolts.

I took the switch out, which is a negitive pressure switch. i.e. when depressed it is off, when released it is on.

I pushed it several times, could here the auto transmission lock releasing. Then unhooked it, looked for abnormal wear and what not. It looked good so i put it back in, ensuring that it was full depressed in the off position. (when the brake pedal is in the resting position, the switch was full depressed).

I hit the brakes several times with the car off, while my GF watched the brake lights. This did create a lot of pressure in the pedal, but when i turned on the car it released.

When i pulled out of my place, everything felt normal...no excessive pressure in the pedal or anything.

Once it started acting up, there was definitely pressure in the pedal.

So maybe it has nothing to do with the switch...and is the cylinder?

The brakes were smoking like crazy...more than i have ever seen...and i have seen this type of thing more than once. after i parked it they continued to smoke, to the point i thought they might catch fire. I know i was risking warping the rotors...but i did toss some water on them after about 10 minutes of smoking. I was worried that if i left them the car might go up in flames...and I had to leave for work and couldn't keep an eye on it.

Majofo

Well I guess $50 a pop for rotors is better than your TL going up in flames. I've only smoked brakes a few times but I've never seen smoking that excessive and never on the TL. There's a continuity test you can do with the bpps.. but I would get a new one since they're fairly cheap. Failed master cylinder that's holding pressure.. could be but I've only encountered failed master cylinders that are leaking or pressure drop not hold.

If the VSA light came on.. I'm thinking brake assist / bpps / something with the external sensors and not a mechanical issue. I'd give it a full inspection now though and change out your brake fluid.

Bearcat94

Dumb question, but the E-brake was off/disengaged, right? For sure?

VSA light is odd though.

Rooster'sTL

Yeah, that is the first thing i checked...it was the front brakes that were smoking too.

There is no such thing as a dumb question, everyone out smarts themselves every now and again.

Majofo

I think everyone has left the ebrake on at least once for a 1/4 mile or so..

Rooster'sTL

So, my roommate just took a spin around the parking lot and said that the brakes seem to be working properly now. The VSA light is off and the VSA button is toggling on and off properly again.

Rooster'sTL

Rooster'sTL

Above is a pic of the caliper...rather toasty!

For them to get hot enough to burn the paint, they must have sustained damage to the rubber in the piston...right?

I hate cars

I had the problem with a different car. Happened more when I did hard braking to the point that the car would barely move.

Try taking the car out first in the neighborhood where you barely have to use the brakes and drive for a while to see if it happens. Then take it out and slam them on a few times and see if they stick. If they stick, it's probably a master/booster problem.

If it happens again, turn the engine off, pump the brakes a bunch of times and turn it back on. If they release, it's a booster problem.

Edit: You didn't notice any ABS-like pulsing, did you?