"BRAKE" dummy light
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Joined: Apr 2008
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From: NAPLES, FL
"BRAKE" dummy light
I have a new problem as of yesterday, and thought it would be an easy fix. I drove the GSL-SE after letting it sit 2 weeks, and the dummy light remained on. I thought I simply needed to change a burnt out bulb, but the lights are working fine. I suspect a couple of areas and want advice please...
1. Lately I have noticed my brake peddle softens while at a light, which I am assuming means the master cylinder is starting to go. I have heard this light will go on if your are low on brake fluid (true?) If so maybe needing to replace that cylinder is causing the light?
2. E-brake works fine, but could it be wearing due to me always parking the car with it engaged?
3. I have heard that if a bulb is "going" but no completely burnt out, the gap in the filiment connection will cause the light to illuminate. The light remained on 98% of the time but did go out for about 1 minute on my way back home, before going on again
As always thanks in advance for any assistance / advice
1. Lately I have noticed my brake peddle softens while at a light, which I am assuming means the master cylinder is starting to go. I have heard this light will go on if your are low on brake fluid (true?) If so maybe needing to replace that cylinder is causing the light?
2. E-brake works fine, but could it be wearing due to me always parking the car with it engaged?
3. I have heard that if a bulb is "going" but no completely burnt out, the gap in the filiment connection will cause the light to illuminate. The light remained on 98% of the time but did go out for about 1 minute on my way back home, before going on again
As always thanks in advance for any assistance / advice
Check your brake fluid level. That light will come on if either the e-brake is on or if you are low on brake fluid. If the fluid level is okay, it is possible that the float that detects low level is stuck, sunk, or wires are shorted.
By far the most likely situation is low on fluid. If this is the case, you'll want to check the calipers for leaking fluid and check the master. The master can leak into the booster, so you might not notice the fluid dripping anywhere. If it is leaking into the booster, you might want to change the booster when you change the master as the brake fluid can ppossibly damage the diaphram in the booster.
By far the most likely situation is low on fluid. If this is the case, you'll want to check the calipers for leaking fluid and check the master. The master can leak into the booster, so you might not notice the fluid dripping anywhere. If it is leaking into the booster, you might want to change the booster when you change the master as the brake fluid can ppossibly damage the diaphram in the booster.
Thread Starter
Joined: Apr 2008
Posts: 286
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From: NAPLES, FL
Thanks
Are boosters readily available? (where?) I might want to change it just to be safe as the car has 160,xxx on it right now and i plan on doing some brakework as well.
Are boosters readily available? (where?) I might want to change it just to be safe as the car has 160,xxx on it right now and i plan on doing some brakework as well.
Joined: Mar 2001
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From: https://www2.mazda.com/en/100th/
there are two lights;
one says "stop lamp" or something, if thats on you have a bad brake light blub
the other light is just "brake" it'll come on if the fluid is low in the master cylinder, or the ebrake is up.
if the ebrake handle is not lifted, then you need to make sure you have fluid in the master.
if fluid is low in the master, one of two things is going on.
1. the system is designed so that with new pads, the fluid is on the "full" line, when the pads are worn out, it will be on the empty line, and the light is usually on. usually this is thrown off because someone tops off the fluid.
2. there is a leak. 1st place to look is the rear of the master cylinder. it'll also drip on the steering box
usually the booster is fine, very easy to test, it should hold vacuum. most places list the booster, but dont actually have em, i had to get mine rebuilt locally
one says "stop lamp" or something, if thats on you have a bad brake light blub
the other light is just "brake" it'll come on if the fluid is low in the master cylinder, or the ebrake is up.
if the ebrake handle is not lifted, then you need to make sure you have fluid in the master.
if fluid is low in the master, one of two things is going on.
1. the system is designed so that with new pads, the fluid is on the "full" line, when the pads are worn out, it will be on the empty line, and the light is usually on. usually this is thrown off because someone tops off the fluid.
2. there is a leak. 1st place to look is the rear of the master cylinder. it'll also drip on the steering box
usually the booster is fine, very easy to test, it should hold vacuum. most places list the booster, but dont actually have em, i had to get mine rebuilt locally
Mine does that from time to time if I take a corner hard. It will just stay on. I have fluid, and the Ebrake is always down. i just chock it up to the Ebrake, even though it is where it needs to be.
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You should replace that Master cylinder. You've done the clutch hydraulics they tend to follow each other. We'll go through the brakes when we do the suspension. Might want to get new front pads, at least. Pretty cheap and they have to come off to do the struts. Looks like we'll have to schedule a work day. Anyone else want to come down and help? It's supposed to get to 80 today.
If you need a booster www.rockauto.com has them for a very reasonable price.
Make sure the ebrake is fully releasing and of course the fluid might be low.
Make sure the ebrake is fully releasing and of course the fluid might be low.
What you call an E-brake is actually a Parking Brake. It is designed to be used when you park. It engages the rear calipers to hold the wheel. If your rear brake pads are worn out your park brake will not work correctly. Using the park brake will not cause it to wear out. Driving with it engaged will wear the rear pads out though.
it was originally called an ebrake. companies can no longer call it that due to legal issues, so they call it a parking break. and yes its just a mechanical brake applicator so to speak.
Thread Starter
Joined: Apr 2008
Posts: 286
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From: NAPLES, FL


Yup....it IS a PARKING brake today. Call me old (school) but have always known it as an emergency brake to be used actually as an emergency back-up in the event the car slips out of gear while parked.
In either event, I am glad you knew what I meant when I used my term...and thanks for your input.
Unfortunately, as a mechanic, I've seen cars that looked like that's how they were driven. I hope you've got everything working now. I'd hate to hear another 1st gen. went to the crusher after the brakes went out.
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