Tail light backup light stays on in all gears.
 

The white square on my tail lights seem to stay on all the time, when the headlights are on.

This started some time after replacing the headlight switch. I'm not sure if that was the catalyst or not. Is there any other explanation?

I dont think its possible i have the two lights mixed up inside.

Are the tail lights on as well or just the reverse lights?

The tail lights are on too. Both top and bottom bulbs are lit.

What year is this? Is this a standard or automatic?

74 F100 explorer - automatic.

Were the lights working before, and did you take it to a shop to have the work done.

My reverse lights aren't hooked up, i took it to a shop to have the headlight switch changed once and when i got it back the reverse lights would come on when i started the truck. They hooked up a wire to see if they worked and never took it off.

I like your idea of just disconnecting the reverse light. It's better than my idea of covering it with red tape. We could all use less red tape in this world.

Im not sure when it occurred, but potentially after i replaced the headlight switch (which i replaced for a different reason.

check local regs, i failed inspection because my backup lights & horn were disconnected. i made the mistake of thinking the huge sign saying "brake tags" meant all i had to have working were my brakes.

i'm like 80% sure that on my 78 f-150 it's a solid green wire, but could be wrong. borrow a cable tracker & you can have this sorted in like 10 minutes.

i have a very similar problem. the right side reverse light is always on. even when the parking and headlights are off. i haven't even begun to look at it yet. any ideas?

The back-up light switch itself is most likely the problem.

Where is the backup light switch on a 1979 F100 located? My backup lights don't work and I'm thinking the switch is the problem.

Auto trans is on side of trans where linkage is attached to trans. it is the same as the nuetral safety switch

thank you for the reply

I got a Backup Light Switch for my 74 F100 but cant figure out where it goes. Would mine also be under the car and next to the tranny?

Is it anywhere near the steering column? i cant find it.

Auto or Manual?