No Tail Lights
No Tail Lights
Ok, the truck is a 77 f-150. I have brake lights until I turn the lights on then I have no brake lights, I also do not have any tail lights. The turn sig. work and every thing in front works fine. I have replaced light switch, and tail sockets. Any ideas on what the problem is? Thanks
I would guess a missing ground by the symptoms.
The brake lamps are using the parking lamp element as the path to ground, only you cannot see the dim glow, as the higher wattage element is lit.
Pull the front and rear bulbs out, and check for ground on both sockets.
I say pull the front also, as the parking lamp circuit is one circuit front and rear, and you don't want to have any other options for a path to ground. ( no rear bulb should cure this, but just a CYA for diagnostics ).
The brake lamps are using the parking lamp element as the path to ground, only you cannot see the dim glow, as the higher wattage element is lit.
Pull the front and rear bulbs out, and check for ground on both sockets.
I say pull the front also, as the parking lamp circuit is one circuit front and rear, and you don't want to have any other options for a path to ground. ( no rear bulb should cure this, but just a CYA for diagnostics ).


