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Emergency Brake Light on Dash

What is causing the Emergency Brake Light on the dash to stay on all the time?

  1. Eminent brake system failure.

  2. Master Cylinder brake fluid level low. Leak in system or more likely brake pads are worn down.

  3. Switch is sticking on E-brake pedal.

Ed B.

The parking brake warning light also serves as a low brake fluid warning.

The owner’s manual will explain this.

It is possible that the brake fluid is now very low if the warning light has been ignored for an extended period of time.

Hopefully, the light has only been on for a short period of time, and as a result the fluid level is not dangerously low–but it needs to be checked and–if necessary–refilled with the correct specification brake fluid. The information on the proper type of brake fluid can be found in the Owner’s Manual–the same book that tells you what an illuminated brake warning light indicates.

A low fluid level in the master cylinder can be the result of either a leak in the brake hydraulic system or because of worn brake pads. As edb stated, this is usually the result of worn brake pads because as the pads wear down, the brake calipers extend and draw extra fluid from the master cylinder. And, this can happen even if impending brake failure is merely of the mundane variety, rather than being “eminent”.

On some S-10s the combination/proportioning/system failure valve turns on the emergency brake light if the fluid pressure of one half of the system does not match the other. In other words, it warns you that you have only one of the two brake systems working. So get the brake system looked at ASAP because if the remaining system fails you and the driving public will be in danger.

Check to make sure the e-brake is all the way off.

Thanks for all the info. Sorry I should have given more myself. I just bought this Blazer last week. I brought it in to get the state safty inspection. They put it on their dyno and said the front brakes work fine. The rear drivers side is only at about 20%ish and the passenger rear is at about 40%ish working. So to me this say’sit’s not the master cylinder.I pulled the rear drums and the pads are good but the drivers side rear pad hangs up when the brake pedal is pushed. I have a new cylinder for it but have yet to install it.
The brake fluid has always been up but it is very dirty. I also blead the system abit but this didn’t help. Sounds like it might be what “researcher” say’s:combination/proportioning/system failure. Any other thoughts now that I came clean with more info???

What year is your Blazer? There will be a wire connected to the combination/proportion/system valve. If removing the connector (temporarily) turns the light out, you now know where the problem lies. If the rear cylinders were leaking, it is possible the system switch has been pushed to one side. Some the these switches were self centering but others required that the opposing system pressure be released to allow the switch to transition to the middle ‘off’ position. It is also possible that the transition plunger is as gummed up as the rear cylinders and the whole valve needs to be replaced.

Hope this helps.