Dashboard lights and Tail lights aren't working but they do work when I press the break pedal

[Apantozo]

I'm totally puzzled. My Comanche is a 1988 and when I turn on the headlights, the tail lights and running lights don't come on, but when I put my foot on the brakes they do come on. Also when I'm towing my trailer, the trailer running lights don't come on unless I put my foot on the brakes. It's not a fuse and  I just replaced the switch clearly not the switch. Where is the ground so I can check it next?

[jdog]

Auto or man's trans?

Ground is behind the driver's tail light

[ghetdjc320]

I know it sounds stupid, but carefully inspect all your bulbs and sockets. 

[WahooSteeler]

  On 8/3/2020 at 10:05 PM, ghetdjc320 said:

I know it sounds stupid, but carefully inspect all your bulbs and sockets. 

Expand  

 

 

I had a bulb not working because the old dialectic grease that was in there had hardened and created a loss of metal contact. You never know......