67 r/t convertible tach and brake light problems

[leroy]

when i turn on my headlights the tach doesn't work, turn off the lights and it works, and when i hit the brakes, the brake lights flicker, what could be the problem?

 

[pnora]

Sounds like two separate issues. The tach is loosing its ground. When you say brake lights flicker I assume the lights in the rear? If so I susspect a ground issue there also.

 

[leroy]

thanks, i will check it