'GC - Emergency Brake Light always on...

Low fluid in master cylinder?

Spdloader

It's probably not the E-brake switch; more likely the differential pressure switch in the master cylinder, indicating partial hydraulic system failure. This is not a good thing and should be remedied quickly. Sometimes these switches must be physically 'reset' after a MC problem has already been repaired. You can check this by pulling the wire harness from the switch to see if the light goes out.

The big red BRAKE light comes on if the parking brake is on -or-

1) There is a leak in the front or rear brake system and the proportioning/safety valve has shut down that side 2) brake fluid is low or brake linings are almost worn out.

I'd start by checking the fluid level and then the disc and drum brakes for wear or fluid.

As the others mentioned it could be a brake failure warning. In my one experience it was a master cylinder seal failure between the front and rear brake systems.

In my WJ the switch was bad.

thanks all. Didn't realize that it was tied into the hydraulic system. My daughter has had the car at college and it was VERY low on fluid (ie no fluid visible) in one of the vessels when she came home for fall break.

I'm sure thats it..

Chip L

Chip L wrote:

There might be a leak or the brake pads worn dangerously thin if the fluid was that low..

Get them checked soon.

Mystery solved. If no fluid is visible, there may be a leak or the brakes are extremely worn and require replacement. The seals in the master cylinder may have also been damaged from the lack of fluid. Have everything examined and serviced before she drives it again.

Something for you to ponder as a FAR more important issue than the braking system on her Jeep: the need to regularly check vital fluids.

Take her aside for 10 mins, open the hood, and show her how to check all important fluid levels, then have her do it while you're standing there to be sure she knows how. This is a very important skill for young ladies to have, and it is an important lesson that parents should teach any aspiring driver.

She really needs an automotive education.

When the Brake failure warning light comes on, the vehicle is no longer safe for the road until it has been determined the failure.

When one reservoir goes empty, it puts serious stress on the seal between the master cylinder chambers which can lead to a 'total' failure there 'very' soon after one goes dry.

When this happens, the brake pedal goes to the floor and the vehicle has only the emergency brake left.

Does she know how to stop a vehicle using only the emergency brake? Does the emergency brake work?

There are other red lights that mean 'stop now' too. One is the oil light another is the temperature light and the other is the alternator light.

The oil and temp can mean engine failure if the vehicle is still driven.

I borrowed a niece's vehicle once and the oil light was on. 'oh is that what that means' was her response as we figured there was only one quart left in the now destroyed engine. It went to the scrap yard soon after.

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail >

Good points all.

We've owned this car since '94. It was OK when she was driving around our small town (high school was a mile away). She is now 2 hours f/ home and uses this 13 year old car to commute and go on weekend trips. I have not been comfortable with her driving the car for several months.

I bought a '99 GC w/ 115k miles last week which we are picking up tomorrow AM. Mechanically, it seems to be a much better car than the '94 has been in a long time (if ever). The service and CarFax check out.

I really appreciate all your input.

Only problem now is that when I pulled the plastic sensor out at the master cylinder, I stripped the entire end off while reinstalling. So the metal plunger and plastic thread are in the master cylinder, but the nut and terminal have torn off. At least I have a few days to get it out....

Chip L

Mike Roma> She really needs an automotive education.

My CJ5 turns the light on depending on the position of the ignition switch. I have to physically roll the switch towards OFF (away from START) to turn the Brake light off.

This light is also used to indicate a problem with the brake fluid level and/or the brake system in general.

Me too.

IF IT HAS SUCKED AIR, then you need to bleed the system before the brakes will be reliable again. By your description, it HAS sucked air.

I truely hate to be the guy that mixes apples and oranges, but many eurpoean countries REQUIRE drivers to be able to identify these vital reserviors and how to get them open. This is an elementary skill to say the least.

It kills me to hear people cal this an Emergency Brake. It is more accurately a Parking Brake. The question is, "does one know how to stop a vehicle using the parking brake?" And, "does the parking brake work?"

There is a huge difference in using the Parking Brake in an emergency and using the Emergency Brake to park.

Up here in Canada if you use the 'emergency' brake to 'park' with at this time of year, you will/might not be 'unparking' until spring.....

The only fix is to be lifted and towed to a warm garage to let the 'parking' brake unthaw so it becomes an 'emergency' brake again.

The number of wheel fires and destroyed brake and wheel bearing systems I have seen from this is too many to count.

I have even had friends use my 'emergency' brake as a 'parking' brake over the years and have had 4 or 5 (that I can remember fast) destroyed rear brake systems because of it 'including' the one on my CJ7 and my Cherokee.

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT's Canadian Off Road Trips Photos: Non members can still view! Jan/06 (More Off Road album links at bottom of the view page

That can be adjusted Jeff. The switch at the bottom of the steering column has slots to set it properly.

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail >

I already have, so you're off the hook. I was taught that fluid levels were to be checked ever time you fueled the vehicle, and the same goes for commercial vehicles. (Actually, with the big truck, we have to do an entire vehicle inspection twice daily.) You'd be VERY surprised at what I've found just lifting the hood of a car once a week!

Here in Kalifornia, Driver's Ed was abolished a long time ago, so that basket weaving classes could get the funding instead. If Arnold ever pulls his head out to catch a breath, I'd love to see him fix this problem.

LOL! Try using the 'Emergency Brake' sometime to actually stop a vehicle in an emergency, and SEE how much worse the emergency becomes.

I'm with you on that one. Driving should be taught at school. We should also teach machine shop, wood shop, construction trades, etc. It is silly to think that all of our kids are college bound. Clearly, some have no business in college.

That's true, but the name of the brake does not make the problem go away. If one uses the parking brake to park OR the emerbgency brake to park, and it freezes shut then life sucks. It is still a parking brake, NOT an emergency brake.