Parking Brake Switch

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1971 Mustang Mach 1, M code, 4 speed.
I'm not really sure if I should post this here in Electronics or in Suspension/brakes etc. but here goes.
My 71 Mach 1 is a low option car, so it did not come with a parking brake switch for a visual reminder light the parking brake is on. To me that ought to have been a no-brainer, but that's Ford for you. Anyway, I did it again (as I'm sure many have) and forgot the parking brake was engaged. Fortunately it was not fully on, but it did heat up the rear brakes to the point I could smell them. No damage done. I've thought about adding some sort of reminder light for some time. The option I was thinking of, is to use the circuit for the redundant distribution block switch and the dash idiot light. The front and rear brakes are completely separated with the rears going through an adjustable valve.
What I had thought of doing is a simple bracket screwed to the parking brake frame and then use a small momentary switch, wired to activate the dash idiot light (I'm the idiot!!). So, today I tried to put it together, but although in theory it will work, I ran into a problem with the bracket I tried to use.
So members, I know there is a parking brake switch available for 71-73's WITH the convenience package, BUT does anyone know if I can retro fit this switch onto my parking brake bracket? If so, that might save me a load of work, but I'm hoping to do it without having to remove the entire assembly.
Here's a few pics of what I tried. In short, the bracket was too thin and bent. Also the switch has to be fully depressed to work.
Thoughts?
 

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Some time ago I started thinking about adding this option as well. I have driven a few times with the parking brake on and I am not too happy about it. I even bought the switch and as I always do it I was going to work back from there. Unfortunately I never got to it. My thought was to use the stock switch and wire it so it lights up the brake light. This is a project I will want to revisit soon so I will follow any ideas.
 
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1971 Mustang Mach 1, M code, 4 speed.
Some time ago I started thinking about adding this option as well. I have driven a few times with the parking brake on and I am not too happy about it. I even bought the switch and as I always do it I was going to work back from there. Unfortunately I never got to it. My thought was to use the stock switch and wire it so it lights up the brake light. This is a project I will want to revisit soon so I will follow any ideas.
Well Tony, I'm glad I'm not the only one!!
Sounds like you want to do the same thing. As said, I was wondering about using the factory style switch which is available IF I can fit it to the bracket on my car. If not, then what I was looking at will work, but with a much stronger bracket. I would also like to source a beefier switch if possible.
 
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Well Tony, I'm glad I'm not the only one!!
Sounds like you want to do the same thing. As said, I was wondering about using the factory style switch which is available IF I can fit it to the bracket on my car. If not, then what I was looking at will work, but with a much stronger bracket. I would also like to source a beefier switch if possible.
For a beefier switch maybe retrofitting a brake pedal switch from another car. Maybe searching Google for break pedal switch and browsing through images until you find one that looks beefier and can be fitted to a custom made bracket. I will look at it tonight to get my brain going with some ideas.
 
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All parking brake housings have the holes for the switch. The problem with using a regular momentary on push button switch is that they make contact only when the switch is fully depressed. This makes it difficult to get the switch adjusted so it consistently provides closure. If it is too far the contacts will not close. If it is too close the brake pedal popping open will destroy the switch when the release handle is pulled. The OEM switch provides closure shortly after it moves from the normal position.

I'm going to do the same thing and have decided to try to find a switch from a newer vehicle at Pik-A-Part to save a few bucks. The repopped switches for our cars are a little pricey ($36 at NPD).
 
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For a beefier switch maybe retrofitting a brake pedal switch from another car. Maybe searching Google for break pedal switch and browsing through images until you find one that looks beefier and can be fitted to a custom made bracket. I will look at it tonight to get my brain going with some ideas.
Good suggestions Tony. We're thinking along the same lines, so between us, we'll come up with a solution. As mentioned, my intent is to tap into the wires to the brake pressure switch and use the idiot light, which at present is not being used.
Also Don C is looking at the same idea.
 
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All parking brake housings have the holes for the switch. The problem with using a regular momentary on push button switch is that they make contact only when the switch is fully depressed. This makes it difficult to get the switch adjusted so it consistently provides closure. If it is too far the contacts will not close. If it is too close the brake pedal popping open will destroy the switch when the release handle is pulled. The OEM switch provides closure shortly after it moves from the normal position.

I'm going to do the same thing and have decided to try to find a switch from a newer vehicle at Pik-A-Part to save a few bucks. The repopped switches for our cars are a little pricey ($36 at NPD).
Thanks for that info on the bracket Don. You're right, the aftermarket switches are expensive, even more for me when I add the current 32% exchange and credit card fee.
When I was trying out my first idea, I did it in the car and believe me, it was very awkward even with the seat out. I'm a smaller guy and today, I hurt all over from the contortions I went through. Next time, I'll likely pull the bracket out, more work!
As for the small momentary switch I tried, you're absolutely right. It only contacts when fully depressed and yes, I broke it. They are just too small and delicate for this job.
I'll go to my local junk yard and see what I can find............. or bite the bullet and buy one.
 

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All parking brake housings have the holes for the switch. The problem with using a regular momentary on push button switch is that they make contact only when the switch is fully depressed. This makes it difficult to get the switch adjusted so it consistently provides closure. If it is too far the contacts will not close. If it is too close the brake pedal popping open will destroy the switch when the release handle is pulled. The OEM switch provides closure shortly after it moves from the normal position.
Why not go the other way? A constant on switch with a relay, when you start closing the switch contact is broken the relay switches on the light, when the brake is off the switch closes and relay turns off the light?
 
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Why not go the other way? A constant on switch with a relay, when you start closing the switch contact is broken the relay switches on the light, when the brake is off the switch closes and relay turns off the light?
Thanks for the suggestion, but I'm afraid that seems a little too complicated for my electronics knowledge. Other's might consider that idea though.
All thoughts and suggestions are most welcome and useful.
 
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Even though a relay doesn't draw much current the current draw will draw the battery down enough in a week or so and it won't provide enough current to the starter for a seldom driven vehicle.

As to the pin switches, they remove contact when depressed, the opposite of what is needed for the parking brake light switch.

The cost to use relays or electronics will likely make the cost of the parking brake switch more attractive.
 
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Even though a relay doesn't draw much current the current draw will draw the battery down enough in a week or so and it won't provide enough current to the starter for a seldom driven vehicle.

As to the pin switches, they remove contact when depressed, the opposite of what is needed for the parking brake light switch.

The cost to use relays or electronics will likely make the cost of the parking brake switch more attractive.
Thanks for the insight Don.
 
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My all time favorite vehicle is our 1969 Shelby GT500
The attached PDF has circuitry schematics and photos that you may find useful re: the wiring aspect of this project.
 

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