Brake Indicator on Dash Issues
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Heel & Toe
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Brake Indicator on Dash Issues
The brake indicator on the dash has recently come on when depressing the brake. I comes on when the pedal is engaged and then goes out when released. A couple of times it does not go on at all when pumping the brakes. Referring to the shop manual I checked the fluid level in the master cylinder reservoir and it is still topped up and fluid color is good. All connections to the master cylinder appear tight. Fluid was changed about a year ago as well as all of the old brake lines being changed out to stainless and there have been no issues. There does not appear to be any leaks in the system. I understand that this lamp will come on when there is unequal pressure between the front and rear brake lines. Is there a possibility that air could somehow have gotten into the lines or could this be an issue with the master cylinder itself??? Any other ideas on what could be causing this? This is an obvious safety concern so don't wish to drive it until I get this figured out. The car is 1992 convertible.
Melting Slicks
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I'd give the system a good flush and bleed the brakes again if it were me.
With these cars, sometimes you have to bleed them several times and then go work the brakes on some gravel some place and then come back and bleed em again.
Given all of the varying methods of bleeding, I've always found the two man method to be the best way to get a nice solid pedal.
I've never had the brake light come on, though, regardless, even with air in the lines.
Could be the master cylinder itself, though. When I replaced my master cylinder, it took three brand new ones that were crap right out of the box before I actually got a good one. Finally went with a Raybestos Element 3 and no problems after that.
With these cars, sometimes you have to bleed them several times and then go work the brakes on some gravel some place and then come back and bleed em again.
Given all of the varying methods of bleeding, I've always found the two man method to be the best way to get a nice solid pedal.
I've never had the brake light come on, though, regardless, even with air in the lines.
Could be the master cylinder itself, though. When I replaced my master cylinder, it took three brand new ones that were crap right out of the box before I actually got a good one. Finally went with a Raybestos Element 3 and no problems after that.
Last edited by Natty C; Jun 16, 2026 at 04:53 PM.
Thread Starter
Heel & Toe
Joined: Sep 2019
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Well, bleeding the brakes to see if there is any air in the system would be the easiest solution. The brakes have been fine for the last year when the stainless hoses went in. They were bled properly and if air in the system is the issue has to be getting in someplace since it wasn't a problem all of this time. Otherwise, as you say. it could be a master cylinder problem. Thanks for your thoughts on this!
Melting Slicks
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Well, instead of perhaps needlessly re-bleeding or replacing the master, start with the very basic checks first. Just to be sure it's not the e-brake partially engaging, maybe engage it and then make sure it's fully disengaged and see if the light comes back on. If it does, jiggle the handle and see if it goes out.
Report back...
Report back...
Last edited by Natty C; Yesterday at 11:34 PM.
Melting Slicks
Joined: May 2019
Posts: 3,274
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From: Mid-Atlantic
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As an afterthought, also make sure that the brake light warning switch is in good condition and plugged into the side of the master cylinder.
I'm not sure whether the light would come on with it unplugged or damaged since the actual function of the switch is to turn the light on and off but worth a check as well anyway.
I'm not sure whether the light would come on with it unplugged or damaged since the actual function of the switch is to turn the light on and off but worth a check as well anyway.
Last edited by Natty C; Yesterday at 11:41 PM. Reason: My spelling is generally good but my typing not so much these days. Heh heh...
