Brake warning light on dash is frying my brain.

pitonegro · April 4, 2012

Hey guys,

I'm having a huge issue with my truck, for some reason I can not get the brake warning light on the dash to go away. It all started while I was driving at the desert (it's a long travel truck). I was taking it easy and I succumbed to my dads peer pressure to abuse it. Thats is when the dash light came on. A variety of other things came up, but ever other issue was fixed. I've exhausted every evil plan to murder this light but nothing does the trick. I changed out every light bulb, I replaced the rear tail lights, I replaced all the brake lines, bled the entire system, checked every fuse, replaced every brake and rotors as well, the parking brake is released, the parking brakes have been replaced, at this point I was thinking of ripping out the dash light but as a mechanic I just can't fail. Now yesterday on the freeway I realized my cruise control is not working either. Anybody have any idea how this could correlate to my brake light issue?

oldscsc · April 4, 2012

Check the switch on the e-brake. If you can easily unplug it, try that. If that was the problem your dash light will go out and your cruise will work again. That's just a hunch...there's lots of other possibilities. Regardless, if the truck thinks either the parking brake or service brakes are applied, cruise control operation is canceled.

Edited April 4, 2012 by oldscsc

AirForceAngler · April 4, 2012

What year, make and model truck do you have? Is it just the Brake light? Or the ABS light? There could be a sensor in the master cylinder reservoir that detects fluid level that has gone bad. May be time for a new master cylinder or sensor.

Morgan1986 · April 4, 2012

Did you try disconnecting the black cable on the battery . To reset things and see if it goes away . The cruise might be a whole different problem. That is the only thing i can think of .

slimjim2525 · April 4, 2012

What year, make and model truck do you have? Is it just the Brake light? Or the ABS light? There could be a sensor in the master cylinder reservoir that detects fluid level that has gone bad. May be time for a new master cylinder or sensor.

X2

Westlotorn · December 5, 2012

I just helped my brother in law fix his last night. Same issue, Parking Brake is released but the car does not know it. The buzzer sounds as soon as you start to drive, the car is in motion.

Buzzer goes off when you come to a stop, resumes as soon as you move.

The Auto light function does not work.

Cruise control does not work.

Solution in this case. New Parking Brake switch needed. I see them on Ebay and Rock Auto for $7.00 so no big deal.

I will check and see if any local parts stores have these. Autozone does have it. $9.99 Part # SW2086 Duralast brand part.

The switch on the 2002 Suburban completes a circuit. When you release the parking brake the circuit is complete and the Parking brake light and buzzer are quiet, the other functions mentioned work again.

To get this car back on the road last night I first tried to run a jumper wire to the switch to ground it, this did not work.

The easy solution is to bend the copper tab back a little so it no longer makes contact with the plastic switch body I did this with a long skinny screw driver, there is not a lot of room. Move the E brake up and down to find the best position to do your work. This made the car think the brake was released and everything started to work normally except for the brake switch which is now disabled. The switch replacement looks very easy, one small bolt and one wire to re connect. There was not room in there to disconnect the wire. that may have accomplished the same thing as bending the copper tab off of the plastic switch body. I think the wire will be easy to remove once I unscrew the one bolt and remove the switch from the parking brake assembly. We will order a new switch today.

AIRTEX / WELLS Part # 1S1925 {#15010522, 15045983, SW2086} Cost looks to be under $10. no big deal.

Edited December 5, 2012 by Westlotorn

ultra680sp · January 5, 2015

I checked the E-brake light switch and it was still good- it flashes if the E-brake is on- the sensor on the brake fluid reservoir was bad on my pickup- it is full but when you unplug the sensor the light goes off- will have to look into it.