1966-67 HCS Brake light switch & no brake lights

[66hcs-conv]

Hi all,

I converted the existing power brakes to a dual master cylinder, and now I can't get the brake lights to work.

I bench bled the new master, and I have bled the lines. I have not started the engine, so the new booster has not had any vacuum applied to it.

The shop manual is confusing as to how to install the brake light switch. I've watch youtube videos and some have the switch wiring going to to the left and some show the wiring going to the right (towards the passenger side).

I would greatly appreciate your help - THANKS ! !

Dave

 

[dalorzo_f]

Would suggest looking at the pedal switch as item #1. Then grounds.

Not familiar with the 66's but on the 68's the wiring goes on from the right. The side would be dependent on if you install the switch with the "U" up or down, I've always installed the with the open end up..

 

[66hcs-conv]

Would suggest looking at the pedal switch as item #1. Then grounds.

Not familiar with the 66's but on the 68's the wiring goes on from the right. The side would be dependent on if you install the switch with the "U" up or down, I've always installed the with the open end up..

THANKS for the help. :smile: I tested the switch & wiring by jumpering the switch & both lights work. Switch itself checks out with ohm meter. I am going to try and add a little shim to the switch, and install the switch as you suggested. Pretty sure the wiring to the right is the way it was.

Thanks again, Dave

 

[66hcs-conv]

added shim

Thanks for the help.

After trying 3 different thickness shims, I was able to get the lights to work with a .020 thick shim. The switch is installed with
the wiring going to the right (passenger) side

Lotas fun "standing on my head" under the dash!

Thanks, Dave

 

[CougarCJ]

That is one of the 'gotchas', power brake and manual brake switches are different.

 

[66hcs-conv]

That is one of the 'gotchas', power brake and manual brake switches are different.

NAPA, O'Reilly's and NPD show only 1 brake light switch for a 1966 Mustang.

 

[CougarCJ]

NAPA, O'Reilly's and NPD show only 1 brake light switch for a 1966 Mustang.

Pretty sure that it has to do with the brake push rod that came with your master cylinder.

 

[Beau66]

I am about to replace a brake light switch on 66 coupe. places I've shopped states for manual brakes only. I ordered one from a mustang parts store which should be here tomorrow. You are right, not much work room.