Dash brake light stays on

[VirginiaCJ5]

I've been driving with the brake light lit on the dash of a 77' CJ5 for about the last AMC 150 miles
What causes the light to turn on?

the parking brake is not on

Thank you.

 

[Torxhead]

At the top of the emergency brake pedal linkage, there is a switch than can stick and just needs to be manually loosened up. If the proportioning valve senses a pressure loss on the front or rear brakes this will trigger the light also, check your brake fluid. Welcome to the forum Virginia CJ5 .

 

[Lumpy Grits]

Welcome
P'brake switch/contacts act'n up(most of the time this is it). When was the last time you ck'd the brake fluid level?
A defective brake proportioning valve can also be the reason.
LG

 

[VirginiaCJ5]

The brake fluid is 1 inch below on one side,and 1 1/2 inches below on the other,and the color is dark brown.Is it ok to just add fluid till 1/4 inch below on both sides,or should I do a flush.

 

[Posi]

Turn the key on and lift the e-brake pedal, did the brake lights turn off?

 

[Torxhead]

That fluid level sounds pretty low and dirty to bet your life on it. I would suggest changing fluid and filling it all the way to the top.

 

[Lumpy Grits]

Fill with DOT 3 type only. That is the OEM type.
Fill the MC, and see what happens.
Better ck ALL of the other fluid levels now(tranny, diffs. t'case etc.).
LG

 

[hdgapeach]

That fluid level sounds pretty low and dirty to bet your life on it. I would suggest changing fluid and filling it all the way to the top.

Probably what Torxhead refers to by "changing fluid" but, if it's "dirty", I'd flush the whole brake system. Takes a little more time but it's worth the extra effort.

 

[elwood blues]

Go to Advance Auto Parts or AutoZone whatever one you have near you that you can "rent' tools from. Rent this thing, its a vacuum pump kit. You hook it to the bleeder at all 4 corners and draw the fluid from the Master Cylinder down to the corners, gets all of the fluid out. And, when you're done, you take it back and get your money back





I just did this over the summer, one of my rear brake cylinders was leaking, so I drained the entire system and started with fresh fluid. It's really not bad to do at all.