brake light on vrs pedal distance

Steve Gallegos · #1 (**permalink**) 01-26-2021, 12:50 PM

I have a backdraft,#595, when I push on the brake pedal the brake light does not come on until I am almost to the end of the distance that the pedal goes. I was told to put a external switch on the pedal arm but if I do that so the switch turns on the light, I wont be able to continue to push the pedal down to apply the brakes. Should I try to bleed the the brakes to see if the pedal comes up higher, or is something else needed?

lnfletcher · #2 (**permalink**) 01-26-2021, 01:50 PM

Put a normally closed switch at the return of the pedal with a return spring to keep it engaged until you brake. Then it will not matter what the travel is on the brake.

cycleguy55 · #3 (**permalink**) 01-26-2021, 04:25 PM

Right, like Infletcher said. Something like this one:

These often have three pins and can be wired either normally open or normally closed. If you look closely you can see the pins on this one are labeled (L-R): C (common / hot), NO (normally open) and NC (normally closed).

Wire it so it's normally closed. The circuit will be open when the roller is pressed against the brake arm and when you press on the pedal the arm will move away from the roller and close the circuit, energizing the brake light circuit.

https://www.digikey.ca/en/products/d...SS-5GL2D/17243

twobjshelbys · #4 (**permalink**) 01-26-2021, 04:43 PM

Be aware of contact current ratings if the lights aren't on a relay. You want a switch not a fuse.

Steve Gallegos · #5 (**permalink**) 01-26-2021, 05:03 PM

what about using a door jam interior light switch?

spdbrake · #6 (**permalink**) 01-26-2021, 05:38 PM

Steve this thread should help.
Member True007 had a good quick fix for a plunger normally closed switch with bracket and PN
Stopped for no brake lights !!

Pics here https://www.dropbox.com/sh/pplph2b2p...n8UXn1oFa?dl=0

Steve Gallegos · #7 (**permalink**) 01-26-2021, 05:59 PM

Thank everyone for the help, getting mechanical switch tomorrow.

cycleguy55 · #8 (**permalink**) 01-26-2021, 08:18 PM

Quote:

Originally Posted by twobjshelbys

Be aware of contact current ratings if the lights aren't on a relay. You want a switch not a fuse.

Yes, good point. I've put a link in to that switch. It's rated at 5A 125VAC - I have no idea what the DC rating would be. Regardless, there are plenty of switches out there that would work.

cycleguy55 · #9 (**permalink**) 01-26-2021, 08:25 PM

Quote:

Originally Posted by spdbrake

Steve this thread should help.
Member True007 had a good quick fix for a plunger normally closed switch with bracket and PN
Stopped for no brake lights !!

Pics here https://www.dropbox.com/sh/pplph2b2p...n8UXn1oFa?dl=0

Standard Motor Brake Light Sending Units SLS66
https://www.summitracing.com/parts/smp-sls66

Probably available at virtually any auto parts store.

Quentin Z · #10 (**permalink**) 01-27-2021, 02:03 PM

Quote:

Originally Posted by spdbrake

Steve this thread should help.
Member True007 had a good quick fix for a plunger normally closed switch with bracket and PN
Stopped for no brake lights !!

Pics here https://www.dropbox.com/sh/pplph2b2p...n8UXn1oFa?dl=0

Great pix! That guy must be a genius!

spdbrake · #11 (**permalink**) 01-27-2021, 06:03 PM

Sorry Quentin is that was your fix and I misnamed it. I remember saving the Dropbox pics link and thought I tagged the genius correctly, lol

IMLost · #12 (**permalink**) 01-30-2021, 03:10 PM

Too many times too many make it far mor complicated than necessary. Simple bracket with a momentary contact switch. 1 bracket. 1 hole, 1 switch. 2 wires. 1 fix. Done go drive.

Steve Gallegos · #13 (**permalink**) 02-02-2021, 01:19 PM

spdbrake, how did you get or what did you use to get the wiring from the engine bay to under the dash through the drilled hole to the switch?

Quentin Z · #14 (**permalink**) 02-02-2021, 02:06 PM

Quote:

Originally Posted by Steve Gallegos

spdbrake, how did you get or what did you use to get the wiring from the engine bay to under the dash through the drilled hole to the switch?

Just disconnect the wires from the pressure switch and leave them zipped up somewhere around there. Use a jumper wire with matching male connections from that point to the new switch. Heat shrink, so they don't ground out & complete the circuit. Drill the hole up from the foot well, and run the jumper wire down through it to the new switch. Crimp on the female ends and connect in to the new switch. Viola.

Steve Gallegos · #15 (**permalink**) 02-05-2021, 04:05 PM

Ok guys, I installed the mechanical switch, did not work, I reconnected the original brake line to the switch on the reservoir , it doesn't work. Do I need to replace the switch? Fuses are good.

Gaz64 · #16 (**permalink**) 02-05-2021, 04:12 PM

Can you post a photo of your switch installation Steve?

Quentin Z · #17 (**permalink**) 02-08-2021, 12:47 PM

Quote:

Originally Posted by Steve Gallegos

Ok guys, I installed the mechanical switch, did not work, I reconnected the original brake line to the switch on the reservoir , it doesn't work. Do I need to replace the switch? Fuses are good.

Do the lights come on when you touch the wire ends together?

cycleguy55 · #18 (**permalink**) 02-08-2021, 01:56 PM

Quote:

Originally Posted by Steve Gallegos

Ok guys, I installed the mechanical switch, did not work, I reconnected the original brake line to the switch on the reservoir , it doesn't work. Do I need to replace the switch? Fuses are good.

When you use an electrical tester, do you have current between either of those leads and a good ground? If not, then you'll have to trace the circuit back to the fuse box.

BTW, when I first received my car (not a BDR) the stop light switch only worked when the ignition was on. Obviously that would be an immediate failure on any safety inspection and one of the first deficiencies to be addressed.