I have an 81 Z28 and the brake lights don't work. The parking lights work and the turn signal/flashers work. Checked all the bulbs and fuses. At this point I think the problem is the brake light switch. (the car sat for a long time before I started working on it)
There are two wiring connectors on the switch. I 'assume' one is for the brake lights. Can someone tell me what the other wiring connector is for??

 

Does the car have cruise?

 

No Cruise Control.
I was able to get the brake lights working by adjusting the brake light switch.
But I'd still like to know what the second connector/wires are for. Maybe something to do w/ the lock-up converter?? (that's just a WAG)

 

The reason he asked about cruise is that newer models can have a second switch to disengage the cruise control.

And auto trans models have a switch to release the converter. I don't have any 2nd Gen references, but the wiring diagrams for 82 models, for example, show a "brake switch (A/T)" that interrupts the 12 volt power to the "converter control solenoid"

 

Thanks for the info. This car did have a lock-up converter. (no more) So that is probably what the wires are for.
If anyone can point me to an on-line, downloadable, wiring diagram for an 81, I'd appreciate it. I've found some, but they haven't been very helpful.