Brake light switch adjustment

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Fab60
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Brake light switch adjustment

Post by Fab60 »

Hey guys so on my mk1 I seem to have issues with the p
Brake pedal engaging the brake lights. I recently changed out the switch to a new one to try to remedy this with no luck. Is there any other adjustments that can be made to have the brakes come on with less tension?? I was wondering if we can wire something up directly to the pedal instead? Safety first right fellas??!! 😁
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Re: Brake light switch adjustment

Post by Polarsilver »

Presume you have the standard Mk1 Brake Pressure switch located on the front Subframe? ..
Or are you talking about your car that has a Brake Switch mounted inside the car on the Pedal Box?

Whatever join the two wires together off the Brake Switch & with Ignition On you should have Brake Lights now ON ?
No Brake Lights & problem is not the Brake Switch ., Yes you have Brake Lights On .. probable is Faulty Brake Switch ..always assuming you have some Hyd Brake Pressure ?
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woodypup59
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Re: Brake light switch adjustment

Post by woodypup59 »

I've had the hydraulic switch go high resistance. It still works but won't sink 3 amps. So I built a small electrical relay system to do the job, mounted down near the pressure switch so you can hardly see it.

You can also fit the later mechanical switch above the brake pedal on the pedal box in the car so that when the pedal goes down, the switch pip comes out and puts the lights on.
finchy533
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Re: Brake light switch adjustment

Post by finchy533 »

As above, the later cars have a little white push button switch on the pedal - it’s pretty straightforward to change a mk1 to this setup, I did it on mine years ago when the original hydraulic switch was playing up.

You can then adjust it to come on right at the top of the pedal travel, which should give a fractionally quicker response. Might just make a difference.
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Re: Brake light switch adjustment

Post by Spider »

Most of the switches on offer these days are quite poor quality. Many have had them play up in a matter of months.

Hella have a good quality Hydraulic Switch, their P/N is 4565.
Fab60
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Re: Brake light switch adjustment

Post by Fab60 »

Thanks guys! Yes my hydro brake switch takes a heavy foot to turn on. Is the relocating switch an easy task?
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LarryLebel
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Re: Brake light switch adjustment

Post by LarryLebel »

If you use silicon brake fluid like me the switches don't last very long. I now have a Harley Davidson brake light switch that has lasted a couple of years.
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Re: Brake light switch adjustment

Post by Polarsilver »

Larry ..Now that is an interesting subject Silicone Brake Fluid .. maybe it does effect the Brake Switch long term reliability :idea:
next time any any of my Brake Switches fail i will cut it open & see what is going wrong.
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Re: Brake light switch adjustment

Post by mk1 »

Out of maybe a dozen or so, I have only ever had 1 brake switch fail & that was a new one straight out of the box. I cannot believe that this is a "common" problem.

I use Silicone fluid in most of my cars.
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LarryLebel
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Re: Brake light switch adjustment

Post by LarryLebel »

I would also like to know what happens to these switches with silicon brake fluid. I figure the fluid can't really contact the pressure switch mechanism because of air in the switch and the switch just operates on air pressure. Here in Canada the switches come from Intermotor Parts. I have a spare one beside me right now. The label says it is made in Mexico.
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