Chevy & GMC Vans

I bled my brakes today using a helper ("pump-the-pedal" method).

After I was done, I wanted to take it out for a spin to check for sponginess but as soon as I started the van, the red "BRAKE" light came on and never disappeared.

At first, I thought I had set the e-brake on so I checked and the e-brake was NOT on.

I took it for a spin and the brakes felt really good. Grabbed really strong and quick. I slammed on the brakes and ABS kicked in like it's supposed to.

I don't know what's going on. Anyone have a clue?

Can I damage anything if I pump too fast and aggressively while bleeding the brakes?

Proportioning valve sets the light. The brakes need to be bled with the pin pulled out.

Smiliesafari wrote:Proportioning valve sets the light. The brakes need to be bled with the pin pulled out.

Where is the pin? and is it safe to be driven with the light on?

Thanks for the response.

The pin is under the rubber cap on the end of the proportioning valve. Over a period of time a lot of junk settles in the valve and will make it stick. They are supposedly a non servicable item. I've disassembled a few and cleaned them and had good luck.

I appreciate the response. Where is this proportion valve? (i.e. Left side of the engine, right side of the engine, over the engine, behind the trans, below the diff...)

Also, any comments on the safety issue? (Just driving it like it is?)

What year van?

2003 Chevy Astro Cargo

I can't say for sure, I think the 1996 and up have the proportioning valve integral with the ABS unit. Such is the case with my '96 Safari. To service this unit you will have to remove the entire ABS unit. I don't know what your skill level is. This is no job for a beginner. The ABS unit is just inside of the subframe under the left side of the van.

Well, what do ya know! the light went out by itself!

I did, after some research, confirm that on the MY2003 Astro, there is no proportioning valve but the ABS does all the proportioning by thresholding the tires. Just a FYI for future reference.

Thanks for the responses guys and gals! I really appreciate it.

Proportioning valve sets the light. The brakes need to be bled with the pin pulled out.

smilesafari ...... can you please go into more detail on this ??? i'm having problems bleeding my back brakes & have the light on also . i'm pretty sure its the proportion valve cuz i have pressure on the lines going into the valve but no pressure on the lines coming out of the valve . this is with the brake peddle depressed of course

Inside the PV there is a sliding piston. It is kept in a neutral position when there is equal pressure on both sides. When it loses pressure on one side the piston slides to the no pressure side and in doing so it lights the brake light on the instrument panel. This is to let you know there is a brake problem. (We already knew that ). To solve the problem you first need to determine what caused the PV to light the light. And to get brake fluid to the side that lost pressure you need to pull the pin that is located on the end of the PV and hold it out until you have pressure where you need it. There is a tool for that. If the PV is stuck it needs to be disassembled and cleaned. Replace the 'O' rings. If you would rather not do that then buy a new one. It's easier and quicker. Find someone with a pressure bleeder. It's the best way to bleed brakes. And the quickest.