Emergency hand brake switch

[kjphilippona]

I had the dash brake light on with the parking brake on or off, it would only get dimmer. I thought the switch had gone bad like everything on this car. Payed $15 for a new switch, replaced the switch and the light would go out when i disengaged the parking brake and come on when i engaged the parking brake. One problem fixed, i thought, today i moved the car and the light is back on, what gives :mad:

[theramz]

Check your brake fluid level. The light will come on if it is low. The lever switch is a grounding switch so check for that too.

[sblake01]

Check your brake fluid level. The light will come on if it is low...

I'm fairly certain that a 77 wouldn't have the master cylinder caps with the fluid sensors. According to the FSM, that didn't start until the 78 model year. That light can also indicate a problem with brake line pressure according to page BR-6 of the 1977 FSM.

[kjphilippona]

Thanks, i am going to do a complete brake system overhaul as soon as i receive all my parts. I was afraid it was not the switch :disappoin

[Zs-ondabrain]

I'm fairly certain that a 77 wouldn't have the master cylinder caps with the fluid sensors. According to the FSM, that didn't start until the 78 model year. That light can also indicate a problem with brake line pressure according to page BR-6 of the 1977 FSM.

I think he was refering to the "Warning Switch" on the block below the MC. I was thinking the same thing but he didn't mention having soft brakes or brake issues, Typically, that switch only activates when the fluid is so low that the driver can actually feel a problem at the pedal.

Dave

[theramz]

I'm fairly certain that a 77 wouldn't have the master cylinder caps with the fluid sensors. According to the FSM, that didn't start until the 78 model year. That light can also indicate a problem with brake line pressure according to page BR-6 of the 1977 FSM.

Your right it's not in the cap but they all have it. It's that little wire coming out of the junction on the frame just below the mc. If this wire is loose or the fluid lever is to low the light comes on.

[kjphilippona]

Sorry guys for not being very clear. The switch i replaced was the parking brake switch, i thought all it did was indicate when the parking brake was engaged. Yes i do have major brake problems, there is a leak somewhere that i cannot find, pedal is firm but brakes do not stop the car very well, also pulls to the left and shakes.

[Zs-ondabrain]

So you need to check fluid levels and check the wire that goes to the junction under the master cylinder. That wire is connected to a pressure switch that is also connected to the "BRAKE" warning light in your speedo. So the Ebrake and pressure switch will both light the warning light in the speedo if there is an issue.

Bleed the hell out of ALL 4 Corners, top off the fluids, check connections and also check the brake pads and shoes.

[sblake01]

Your right it's not in the cap but they all have it. It's that little wire coming out of the junction on the frame just below the mc. If this wire is loose or the fluid lever is to low the light comes on.

I know what he's talking about. It was your statement that made it unclear. I think you need to read the FSM again. Read the differences between the brake warning systems in the 77 and earlier vs the 78 and later. 77 and earlier had the brake indicator switch located beneath the MC. If the fluid level was low enough to not reach that switch, you'd have lost your brakes long before. It has nothing to do with monitoring the fluid level. That was the purpose for changing the system for the 78 and later models. On the 78 and later models, a simple three way connector replaced the switch below the MC and the level monitoring caps were added. I was just trying to make sure that we're all talking about the same thing.

[theramz]

First of all you need the correct FSM for the year. He didn't mention what year. The question was why his the warning light stays on. My light on my '77 was on and when I added fluid it went out. Just offering a posible simple solution to a problem without taking the car apart.

[sblake01]

I did take the time to find out that his is a 77 which is why I used that in my posts. I really don't want to argue with you as I don't have anything at stake here...I know what I know and you know what you know. I'm just trying to help him solve his problem also. He say's he has other brake problems. If putting fluid in solves his problem, I'll be the first one to give you kudos. Otherwise, I'll say nothing else here.

Edited November 9, 2009 by sblake01