Brake warning light - what does it do

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AuroraGirl

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Lmao. ^

a choke heater is a thing.
Same.Circuit.

But what does that have to do with oil pressure?

Same circuit?

AC compressor safety switch included?

+ OE trailer brakes?

Look, what i'm sayin is all that stuff shares the same circuit -I think - and a problem in any of those systems may trip that light..I think...but if you have brake fluid LEAKING, you should fix that first.

I have to say "i think" or these muggs will chew me up but it doesn't really matter because i'm right anyways...I think. ;)

The question is about the light?

Axe @chengny and get lucky if he shows up..he has pictures!
hay buddy!

:wave:
I DONT have a brake light on is what im saying. As in, I think it should be on because I frequently have no fluid in rear brakes, whats the reason yall thinks
 

77 K20

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I DONT have a brake light on is what im saying. As in, I think it should be on because I frequently have no fluid in rear brakes, whats the reason yall thinks

If I remember right the factory combo valve/proportion valve has a rubber boot on the top of it. This boot only has one wire in it. When the factory combo valve detects a problem (pressure loss) a metal piston inside moves to one side. This grounds out the pin coming out of the combo valve. If you have a meter check a few things. Pull off the wire and check the pin of the combo valve to frame ground. And/OR you can put the wire you just pulled off to ground. This should then turn on your brake light in your dash. If that doesn't do it... then burned out bulb? Your wire is broken/disconnected somewhere?
 

Rusty Nail

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That stupid green wire can be the bane of existence - I swear.
Lmao gotta love it?

Jerry will eventually pop in and disseminate drawrings upon thee.
All that safety stuff is on one circuit though..it gots a fuse somewhere...he always knows, and im just a schmoe.
 
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75gmck25

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On my truck there is no sensor to tell you the emergency brake is on, so the dash brake light is only for the braking system.

To test the brake Warning light I just turn the ignition to on (not to the start position) and the brake light is steady on. If it does not light up, the light bulb or circuit is bad.

When I first got my truck the wire on the prop valve was broken, and the ground wire for the instrument panel was disconnected. Things get broken on old work trucks.

Bruce
 

AuroraGirl

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On my truck there is no sensor to tell you the emergency brake is on, so the dash brake light is only for the braking system.

To test the brake Warning light I just turn the ignition to on (not to the start position) and the brake light is steady on. If it does not light up, the light bulb or circuit is bad.

When I first got my truck the wire on the prop valve was broken, and the ground wire for the instrument panel was disconnected. Things get broken on old work trucks.

Bruce

OH so thats the wire that my quart of ATF fell onto and pulled off that I couldnt figure out what It did. Im guessing its factory routed properly or with conduit. Mine was about 5 extra feet dangling oon the fender zip tied in a bunch. Not sure what my gpa was doing there... but Okay. And it stopped working before that, but I also blew a fuse for soemthing that i couldnt ever figure it out functioned for, so I just ignored it. Does the fuse control the choke, 4wd, seatbelt, and brake warning lamps, perhaps?
 

Blue Ox

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I start plenty of threads. I also don’t feel ignored on any questions I post. And I’m not specifically attempting to “piggyback” on HER threads. I add info or bump threads with related questions I may have to increase views of her or others threads as well. Don’t like it? Welcome to the internet. Plenty of alternative opinions out here I’m thoroughly happy to hear yours. If I have violated a rule please point it out to me.
Good evening sir

Well, since I think this is where the question came up, and I happen to have a squarebody in my back pocket, here is a pic of the factory switch in my '85. It's the white block at the top of the photo with the brown wire connected. The brass looking tab is what trips the microswitch. Hope this helps.

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gotyourgoat

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Start your own thread , we have plenty of room. You always piggy back on her threads and it's not cool, that's why nobody ever answers you.

Welcome to the internet.
Hello internet.
;)
 

Rusty Nail

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OH so thats the wire that my quart of ATF fell onto and pulled off that I couldnt figure out what It did. Im guessing its factory routed properly or with conduit. Mine was about 5 extra feet dangling oon the fender zip tied in a bunch. Not sure what my gpa was doing there... but Okay. And it stopped working before that, but I also blew a fuse for soemthing that i couldnt ever figure it out functioned for, so I just ignored it. Does the fuse control the choke, 4wd, seatbelt, and brake warning lamps, perhaps?


There may be a super crappy
Spade terminal on that steering wire that looooooves to snap off. The base is Smaller diameter than your pinky.

And im sitting in a Honda, dont be mad...:(
@Blue Ox with the pix makin nickels look bad.
 

80BrownK10

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Oh, I have a leak all right. The rubber from the block on differential to the wheels leaks a lot, the wheel cylinder passenger rear keeps the wheel wet with fluid, and the steel line at the mounting tab just a few feet before the block on differential shoots it out, too. but the light only comes on once in a great while, typically if it sits emtpy for a week. Proportioning valve or wiring maybe bad?
I think you have pinpointed your problem;):happy175:
 

80BrownK10

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Oh no, this leak sprays and it hemmorages at the three points.
You do realize how important brakes are right?o_O:33:

If you have puked all your brake fluid out and go to step on that petal at 50 and nothing happens....you better hope your parking brake is adjusted up and you think fast and it's strong enough.
 

AuroraGirl

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You do realize how important brakes are right?o_O:33:

If you have puked all your brake fluid out and go to step on that petal at 50 and nothing happens....you better hope your parking brake is adjusted up and you think fast and it's strong enough.
What is a parking brake?

Jokes aside, physically it exists but it is seized in the open position. So not working.

And, its only the rear brakes that leak, the fronts are almost there on the hoses but not quite.good thing i dont drive onroads
 

75 short

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i also have a 75 owned since new and my light does not come on when e brake is on only comes on when key is turned on
 

AuroraGirl

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Well I think I found my issue.. must have forgot it was no longer gonna be working.

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