The brake engages the starter?

I have a 1987 F150 4x4 with the 5.8 and it’s an automatic.

When I depress the brake, the starter engages.

This started happening on a trip to town, I had been driving around all morning with out any problems, I pulled up to a stop sign, and it started. When I pull the fuse for the brake lights the problem goes away, so do my brake lights.

Any advise would be appreciated I have replaced the ignition switch and starter.

I burned out the starter trying to get to a parking lot to figure out what was going on.

Thank you


Boy…someone did some creative wiring on that puppy. You didn’t say, but is this a recent purchase? If so, check with the seller…if a dealer…demand they fix it. If private party purchase, ask if there was any electrical work done on the vehicle, and try to determine which wires are crossed…which they obviously are somewhere. Good luck.

I bought this rig from a company I used to work for. I have been around it for the last 10 years or so.

I also have been driving it for quite a while before this happened, it seems to have come out of the blue.

Short circuit.

The wire that connects ignition switch to starter relay is red/light blue stripe.

the wire from the brake light switch is light green.

Looks like the insulation of these 2 wires has rubbed off & they are shorting together under the dash near the brake lever arm.

Thank you for that advise, I will trace those wires and look for shorts.

I’ll let you know what I find

Glad I could help & good luck with it.