I learned something new last week while working on my truck. I had fixed the back of the bed with a steel sheet and moved the truck back into the driveway, but when I hit the brake my dash and running lights come on. So I checked the wiring at the back where I had installed the plate and found nothing wrong or pinched. So I started checking everything from wiring under the dash to the trailer plug. 3 hours later I pull the tail lights to check the wiring on the back of them, unplugged the right tail light assy and it quit. Turns out I blew a 1157 bulb, but when I did, the piece in the bulb touched the running light side. At least my wiring is good..

 

Yeah, i honk the horn and my truck starts up.

 

bad ground 1 prob

and the horn thing you have a short in ignition system i think but do you have an aftermarket alarm

 

you know how the light has the running and brake in the same bulb, one filament wire melted and touched the other is what happened.
Now if your serious about your horn starting the truck , cool...

 

yeah bad ground for the lights do that all the time wire will get hot melt ground wire and will do weird if it was a power short lite wouldn turn on

 

Wow and I figgered I was the only one with funky wiring on my 89 Yota.

Started out the brake lights didn't work. Found bad wires and a bulb, so fixed the issue.

Now, a day later. the brake lights don't work when the Head lights are on (but they work without the head lights on).

Oh yea, dash lights come on when I push on brake (also a new one)/

Anyway, off to try out the ideas everyone has posted.

Will let y'all know the outcome. Thanks in advance for being here.

 

This is the 84-85 section... You may have better luck in the next group over... The 86-?? folks.

 

Thanks, still trying to trace the problem. Changed bulbs didn't go any good.

Sure would have been nice if Yota would have put in 1157 bulbs rather than the 1156 single fulfillment bulbs. Individual circuits are sure better then the one.

I had an old Chevy with the same problem. It turned out to be wire in the steering. A wire shorted out causing the same problem. But that was horn honking and dash lights coming on every time you hit the brakes. Sure were a lot of ticked off people at stop lights

I also had a Nissan 4x4 doing the same thing. It cost $100 to replace the whole modular unit on the steering. But it fixed the problem.

Oh well, shouldn't rain too much where i'm at in Oregon today. So time to crawl around outside the cab rather than crawling the way we like it.

Anyway. Thanks for the reply.

PS: I'm really leaning in the direction of a ground. Just finding it...oh what fun

 

I'll be darned. It was a shorted out bulb.

 

I just had this happen to my truck. My truck is a 1985 Toyota 4x4 pickup. I did a walk-around outside of the truck and did not see any lights burnt out. Any suggestions? I am going to check the bulbs when it is daylight outside tomorrow. Any help would be appreciated since I am not that electronically inclined.