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Brake light on dash and no cruise control

Posted: Tue Dec 04, 2018 3:20 pm
by Yembo77
I had this issue in the past in a tahoe and trailblazer...

The brake light appears on the dash, the cruise doesn't work, and the brake lights on the exterior also don't work. In the past it's been a quick stoplight switch replacement and it's fixed, BUT on the PPV, my brake lights still work? Only my cruise is out and the "brake" warning light is lit on the dash.

Am I on the right track? The ABS light is NOT on. I thought it might be the abs controller but with the cruise not working I'm thinking it's the switch.

Any help or experience in changing this on a 12' PPV would be great.

Thanks,
Matt
Denton, TX
2012 Caprice PPV/Holden CapriceV
1970 El Camino SS

Re: Brake light on dash and no cruise control

Posted: Wed Dec 05, 2018 5:31 am
by Jaked1985
Is your ebrake depressed a couple of clicks?

Re: Brake light on dash and no cruise control

Posted: Wed Dec 05, 2018 3:00 pm
by Mooseman
Do we have a brake fluid level sensor? Could be that or the level is low.

Re: Brake light on dash and no cruise control

Posted: Tue Mar 19, 2024 1:23 am
by kay_y
Hi,

I have faced the same problem , my parking brake light is on at dash , cruise not working , Brake oil level is okay , No problem in braking system. Every thing seems fine except the two mentioned above .. Can you please guide how you got rid of that problem in your car .

I have Caprice 2012 - V8 6.0 with 115000 Km on it.


thank you.

Re: Brake light on dash and no cruise control

Posted: Tue Mar 19, 2024 9:15 pm
by Sanford
Hook up a decent scan tool that will show the live data on all 12 modules. It might show you something. Never have had just the brake light on any of my fleet of 11-13’s, so no personal experience.

Re: Brake light on dash and no cruise control

Posted: Wed Mar 20, 2024 12:25 am
by kay_y
Sanford wrote: Tue Mar 19, 2024 9:15 pm Hook up a decent scan tool that will show the live data on all 12 modules. It might show you something. Never have had just the brake light on any of my fleet of 11-13’s, so no personal experience.

It gives brake booster pump error to be specific i need to recheck the code, but I'm not facing any problem in braking system other than that light which appears on my dash or when i need cruise.

Re: Brake light on dash and no cruise control

Posted: Wed Mar 20, 2024 12:19 pm
by Lord Vader
Does the third brake light on the rear window still work? I seem to remember something about the cruise control circuit going through the high-mounted stop light.

And check the switch on the emergency brake. Are your daytime running lights on?

Re: Brake light on dash and no cruise control

Posted: Wed Mar 20, 2024 9:43 pm
by JoeR
The service manual says 2 things turn that light on. The paring brake and the fluid level switch.
If the fluid level is low, or if the fluid level switch is unplugged, the lamp will come on.
Fastest way to diagnose it would be to grab a scanner, check the parking brake switch state in the Body Control Module. If the BCM shows it is set, then you're chasing a parking brake switch problem. If not, it's fluid level, fluid level sensor, fluid sensor wiring.
I'm not positive what voltage the cluster provides to the fluid level switch, but it's gonna be battery voltage or 5V. I'm betting 5V when it's unplugged. When you plug it in, it should drop, but not to 0V. 0V or something close means it sees low fluid, or the switch is shorted.
If the voltage doesn't drop when you plug it in, check the ground wire.
Joe

Re: Brake light on dash and no cruise control

Posted: Thu Mar 21, 2024 6:40 pm
by Sanford
Have you cleared the vacuum pump code? I believe the pump only runs a little while during cold start-up. Have you checked to see if the pump runs?

Re: Brake light on dash and no cruise control

Posted: Sun Mar 24, 2024 12:18 am
by kay_y
Lord Vader wrote: Wed Mar 20, 2024 12:19 pm Does the third brake light on the rear window still work? I seem to remember something about the cruise control circuit going through the high-mounted stop light.

And check the switch on the emergency brake. Are your daytime running lights on?
Yes The Every thing else fine except the cruise.