I have a 71 cutlass 4dr and for some reason the rear lights will not shut off. I have to just unplug the whole setup because they will stay on with the engine off keys out and all. Yet the signals work and they get brighter when i hit the brakes. The front lights will shut on and off as usual. Any idea why this is happening?

 

I had this happen to me twice.
First time, The shop that flushed my coolant and rear differential fluids installed the wrong light bulbs in the taillight sockets and they were shorting out. I appreciated them going the extra mile and doing that for me, but.....

The second time, The stop light switch behind the brake pedal shorted out.

 

If the tail lights are on when the headlamp/tail light/interior dimmer switch is in the off position you may have a bad switch. There should be no 12 volts available to the tail light socket at all with the switch in the off position (except when the brake pedal is depressed). For the lights to be on and get brighter with the brakes applied you would need both a bad brake switch AND some wrong lamps installed in the sockets.

 

Everything on the car has been there for months i havent changed any bulbs etc, but i will look into the the switches and see if thats the problem thanks