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1970 new wiring harness, have question about brake switch
Anyone have a brake switch picture or know where i can source a new one ???
I swapped my 2 pedal assembly out with a 3 pedal as I'm converting to a 6 speed manual.
I also gutted the factory 1970 harness and tossed it, and putting in a new 21 Circuit harness.
I'm stuck on this part, because I know I need the switch but can't find my old one.
I'm just not sure how the brake wiring is supposed to be setup to ensure my directional signals still work while applying the brakes.
I did another GM classic and I forgot something and the brakes would block the directional signals.
I can't remember what I forgot last time that I corrected after to get them to flash with the brakes applied.
I'm assuming it has everything to do with this switch ??? Correct ???
Last edited by Aceshigh; July 30th, 2017 at 04:02 PM.
Should be able to get one at your local parts store. Is your harness a generic replacement with a diagram? You can look at any A body wiring diagram and see how the brakes and signal lights are interconnected.
I have a classiccarwiring.com 11x17 factory harness colored schematic,
but it's unclear to me how the brakes don't override the directional signals and stay solid. (Like I said ,I had this happen to me on my last rewiring of a GM classic and I figured it out but I forget what it was)
The new harness is an EZ Wiring 21 circuit harness but the instructions are terrible.
Harness and fuse block are great, it's just not easy for anyone just doing this for the first time.
I did an American Autowire harness on my last GM classic and the schematics were simple to follow.
This is just a blip on my radar trying to make sure I get it done right.
Is this switch mounted by column like this picture ??
I put one of those kits on a 32 ford coupe hot rod. They don't use a wiring diagram per se, but its pre wired for the brake switch, signal stat, and the steering column harness. All the wiring is stamped as to what they are for. Pretty simple actually.
Yeah it has 2 wires that goto the brake switch that are labeled on the wires.
I just couldn't remember how it overrides and allows the signals to flash during braking.
I guess I'll hook it all up and then troubleshoot if i need to again.
Yeah it has 2 wires that goto the brake switch that are labeled on the wires.
I just couldn't remember how it overrides and allows the signals to flash during braking.
I guess I'll hook it all up and then troubleshoot if i need to again.
The brake switch is just an on/off switch. The control of brake input vs turn signal input is done in the turn signal switch. A single wire from the brake switch provides power to the turn signal switch when you step on the brakes. If the turn signal lever is not actuated, this power from the brake switch is routed to the turn/stop filaments in the 1157 bulbs. If the turn signal lever is actuated, the contact in the turn signal switch for THAT SIDE ONLY disconnects from the brake circuit and instead connects to the signal from the flasher module. The other side is untouched.
July 30th, 2017, 03:59 PM
