My electrics have been possessed

Hi, wondering if this is a problem that anyone has encountered before and if so, did they get to the bottom of it?

I have a 66 Beetle that last Monday decided to go the the dark side. The stop lights stay on all the time. Well most of the time. Let me explain.

When starting from fresh, battery reconnected all is well, brake lights off. Can turn on parkers and headlights all good, tail lights come on without brake lights.

If I then turn on the ignition and apply the brake, the brake lights come on. I can then take my foot off the brake pedal and the brake lights stay on. I can even turn the ignition off and the brake lights STILL stay on. Only way to fix this is by disconnecting the battery.

Have checked connections at the brake lights and all seem good, no obvious signs of issues with the cables to both brake lights. Have also replaced brake switch at master cylinder just in case.

Any suggestions greatly appreciated.

It has to be a back feed possibly from something with a bad earth as the brake light circuit is fed through the ignition as are the flashers,wipers etc. Look to what extras have been added.i.e. radio, stereo etc.

awesome, thanks Grumble, you have inspired me back to the shed. I installed an old PB radio about 3 months back, will suss the earth. Another possibly unrelated symptom was the ignition would not switch off today until I snuffed the engine with the clutch. Lots of earths to check...

Thanks again for your assistance Grumble, dodgy earth found, problem gone.

Sargo wrote:Thanks again for your assistance Grumble, dodgy earth found, problem gone.

Glad that some of the grey matter is still working and it helped, a few years ago I spent days looking for problems in a Golf wiring
and the previous owner just added extra switches, wires or whatever when something didn't work. I brought a s/h loom and rewired the little golf, it was a nightmare but logic usually finds the fault.