Brake light on dash and no cruise control

Electronic systems, stereo and Holden iQ, wiring, it all goes here....
kay_y
Posts: 6
Joined: Mon Mar 18, 2024 12:40 am

Re: Brake light on dash and no cruise control

Post by kay_y »

JoeR wrote: Wed Mar 20, 2024 9:43 pm 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

Actually the major issue is that is does not appear on scanner too , I have checked yesterday nothing appeared on scanner. As i remember it could be related to brake fluid level sensor , because when it started to appear, I topped up the brake oil to required level and it went away but then after some time it appeared again and brake oil level was okay.

Is there any switch , sensor under the handbrake lever inside the car ?
smwalker
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Joined: Mon Jul 29, 2013 1:44 am
Location: Azusa,CA

Re: Brake light on dash and no cruise control

Post by smwalker »

There is a fuse for the cruise control. Is your car still all factory or did someone do a Center console conversion?

https://appcontent.chiltonlibrary.com/c ... 662660.pdf
cruise control 12 ppv.png
cruise control 12 ppv.png (141.92 KiB) Viewed 112 times
Shows F9 as the fuse. But it should be ok because there are other very important things on there.
Don't think you would even run if it was blown

https://appcontent.chiltonlibrary.com/c ... 609169.pdf
Steve Walker
Azusa, CA
'11 PPV 9C3 Huron White
kay_y
Posts: 6
Joined: Mon Mar 18, 2024 12:40 am

Re: Brake light on dash and no cruise control

Post by kay_y »

The Caprice is totally Managed by the Company for all services almost, never went for any major maintenance job other then oil change.

Coming to the Fuse , to my understanding fuse are connected to transmission control as well that is working fine, but still i will double check the fuse.

The function of cruise is not working because of brake light and notification on dash.

I have showed some local technicians they advised me that there is a problem with ABS module probably . I denied it but i will ask my agency to check it.

What your take on it ?
kay_y
Posts: 6
Joined: Mon Mar 18, 2024 12:40 am

Re: Brake light on dash and no cruise control

Post by kay_y »

JoeR wrote: Wed Mar 20, 2024 9:43 pm 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

I want to check this i have volt meter .. if you not mind can you guide me how i can check the switch. Where exactly fuel level sensor is , if im not mistaken it is under the fuel reservoir .
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