Hello, I recently got an 88 EFI pickup and it has an oddness with the lights.
It's a base model, I think, if it matters. Seems to be stock all around, even tape deck, lol.

Symptoms:

1) (while lights are in "off" position) I press brake pedal = brake lights, gauge lights, running lights all come "on."

2) (while lights are in "on" position) All lights are on, even brake lights! (even without pressing pedal.)

So, has anyone actually had this same problem?
I was asking now to possibly same some fumbling time, but I'm going to investigate in the AM, too.

Thanks in advance,
JR

 

Does your truck have a trailer wiring harness on? if it does start there the po might have crossed the tail lights with your running lights. simular thing happened to me. If not then start checking for wires that have been taped into for any reason and make sure they are not crossed. thats just my 2 cents.

 

I'd guess one of the brake light bulbs in the rear is either corroded or installed wrong, crossing the brake and marker light terminals together.

 

Well, it warmed up a bit yesterday, so I did some more snooping. I guess actually, the only odd thing is that when I hit the brakes, the running & gauge lights come on. Other than that, all the lights work normally. No trailer harness, either. I think in the spring I'll get into this more, but for now, it's fine! Thanks for the suggestions!
Best regards, JR