Parking Brake Light Stays On

[RB72]

Does anyone know why my brake light on my dash stays on even after I release it?

[geezer#99]

Maybe that brake light isn't for your park brake!!
It's for your prop valve! Tells you you have a failure in your master cylinder.

[franken]

Pull up on the parking brake pedal and see if it goes out.
It could also be an indication of brake problems.

[leftybass209]

Originally Posted by RB72

Does anyone know why my brake light on my dash stays on even after I release it?

These trucks were not equipped with a parking brake indicator. The light you are seeing, as geezer said, is to indicate a fault in the hydraulic aspect of your braking system. Sometimes it comes on due to an incorrectly bled system, or it could be reading that you have a leak and have lost pressure somewhere.

On a side note, there is a diy thread on the forum on how to make the brake light function with the e brake. It's a really cheap and easy mod.

[LockDoc]

-
As the others have said that light has nothing to do with your parking brake. Take the cover off of the master cylinder and I will bet that one of the fluid chambers will be dry. That means you have a leak in either the front or rear brake lines or wheel cylinders.....

LockDoc

[RB72]

Originally Posted by LockDoc

-
As the others have said that light has nothing to do with your parking brake. Take the cover off of the master cylinder and I will bet that one of the fluid chambers will be dry. That means you have a leak in either the front or rear brake lines or wheel cylinders.....

LockDoc

You were right my chamber closest to the cab was dry!

[LockDoc]

Originally Posted by RB72

You were right my chamber closest to the cab was dry!

If you don't see any fluid leaking from any of the rear lines you will have to pull the rear drums off to see which wheel cylinder is leaking and replace it.... Wait! Is this a C-10 or C-20???

LocDoc

[RB72]

Originally Posted by LockDoc

If you don't see any fluid leaking from any of the rear lines you will have to pull the rear drums off to see which wheel cylinder is leaking and replace it.... Wait! Is this a C-10 or C-20???

LocDoc

It is a K10!

[LockDoc]

Originally Posted by RB72

It is a K10!

OK, I'm not sure which chamber is the front and which chamber is the rear on those. Some of them are the opposite of what you think they would be. I'm still thinking the front one is for the front brakes and the rear is for the rear brakes on the 10's.....

Let us know what you find out on it.

LockDoc

[tommys72]

My light is one too, rear reservoir is almost empty. Investigated a little more, both rear wheel cylinders are leaky! Not so good...thanks guys