walker39

Last night, when accelerating quickly (roughly 80% throttle) to get onto the highway, the parking brake light came on briefly. Once I stopped accelerating and the speed leveled out, the light went out. I've noticed this has happened the last few times I have accelerated hard.

It didn't feel like the brake actually engaged, but the light is a little concerning. Anyone had this happen to them, or have any idea what could be causing it?

I have a 2010 base model sedan, lowered on eibachs, with an R2C CAI, and I use the parking brake every night, since my driveway has some slope to it.

Thanks in advance

ANMVQ

iTrader: (13)

Check you brake fluid, If its low when you go WOT the fluid will move away from the sensor and the light with come on. It been said on here before too

walker39

Thanks ANMVQ, I'll check that out today after work.

AUR11

Yup what he said, I had the same issue and topped off the brake fluid and it was fine. Although you should keep an eye on your pads as it is a sign of needing replacement soon.

pontiacstogo

iTrader: (1)

Mine did the same thing this morning on the way to work - 25K miles so I guess pads are worn enough for the fluid levels to drop. I'll top up tonight.

walker39

Brake fluid on mine is full, so the pads would seem to be the culprit. The brakes squeak a little in the morning when I first drive the car, so they probably need to be changed.

Thanks for the help

pontiacstogo

iTrader: (1)

Low pads wouldn't make the warning light come on if the master cylinder was full of fluid.

The problem you described (brake light flashes under hard acceleration) is much more indicative of fluid being low in the master cylinder reservoir and temporarily triggering the low fluid warning.

Fluid gets low as pads wear because the fluid needs to take up the space in the calipers/slave cylinders as the pads compress. But that's normal, and topping up the fluid should stop the light from triggering.

walker39

That makes sense, pontiac. The fluid level is right at the "max" line right now, but topping off the fluid above that line shouldn't be an issue, right? Sorry, I'm not too knowledgeable about the brake system (haha, as you may have figured out by now)

VT's G35S Sedan

iTrader: (3)

When the Brake warning flashes, does the Slip and VCD come on after if you don't let off the throttle?
I had that and if this happens when you are turning either left or right= Front Speed Sensors( Remove wheels and then take them out and clean them and also make sure the screws holding them down are not oxidized, plus the holes in which the sensors sit in)

If this Brake light flashing comes up when your WOT up a hill or straight line= The rear speed sensors need to be checked. remove, clean and reinstall).


So far I had this on both of my sedans and the first one would do this when WOT from stoplight and turning left or right. My second(current) sedan did this when ever I would WOT 50% of the time in a straight line but 100% if I WOT up a hill.

Good luck hope my experience with this problem helps.


Here is a picture of how I found the front sensors-



here is a pic of the front sensor after I cleaned it up.

walker39

Wow, I didn't even know we had speed sensors in the front and rear - definitely good to know.

To answer your question, neither the slip nor VCD light come on at any time. I havent noticed if the Brake light comes on during cornering as well, but I know straight-line acceleration results in the light flashing (with or without a hill).

Adding brake fluid has fixed the light-issue for now, but I will definitely clean out the sensors the next time I rotate the tires. Thanks VT

Lokosis

I know I'm bringing back a dead thread to life, but I want to add my 2 cents since it helped me, and it could help someone else in the future.

When slowly going uphill, either from a stop or a red light. Red brake warning light would come on followed by the VDC light, red light goes off, but the VCD stays on until i restart the car.

Checked if parking brake was up, checked brake fluid, all good.

Unplugged the brake fluid sensor under the reservoir, no lights anymore. Now I know this isn't the best solution since if I am low on brake fluid I won't see a warning, although I'm sure I'll feel it with a long brake pedal. But having it unplugged keeps my VDC on if I ever need it.

brizey

Hmmm...going to have to check my speed sensors. Doubt my brakes are gone after maybe 12K, but I have not checked them either.