I need help with this. I just change my power booster on my 68 mustang and the brake lights are not coming on. I notice that this push rod in the center has a nylon shim and the org didnt. When I put the stop light switch in, I notice one side is on top of the shim. Does both side of the stop switch need to touch and make ground. Iam lost and I cant figure what I did wrong. If any mustang techs knows anything lt will be appreciated.
The switch does not need to be grounded to function.
The two steel legs of the switch have to be outside of the nylon sleeve in order for there to be enough movement to actuate the switch.
There are two different switches for the 68 depending on whether you have power or manual brakes. The difference is the spring pressure; the power brake switch actuates with lighter pedal pressure.
Two things to try.
1) Remove the switch, cross the connections in the plug. The brake lights should come on. If they don't, check the fuse. The only other item in the circuit is the turn signal switch. It can affect the brake light circuit but it's a slim chance it's involved in this problem.2) If crossing the wires makes the brake lights come on, then put the switch back on the pedal but leave the nylon top hat bushing off. This will increase the amount of travel available to push the switch plunger and will not compromise the integrity of the brakes.
What you described is normal. The brake lights should stay on steady with the brake depressed. Have you checked to see if you're getting 12V to one side of the brake switch? The other side should show no voltage assuming the turn signals and emergency flashers are off. I don't have my schematics handy, but I recall the emergency flashers being fused off the cigar lighter circuit and the brake lights off another fuse.
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