New Poster, Searched the FAQ and Advanced searches to no avail. 1997 f150, 4x4, 4.6L 320,000km. With headlights lights off, turn signal blinks faster when applying brakes. With headlights lights on, turn signal blinks faster all the time(without applying brakes). Brake lights not working, Reverse lights not working, Brake light on top of cab working. Several weeks ago, thought it might be the brake light switch(the one attached to the brake peddle) Removed switch, reinstalled same switch, Walla, everything working. Thought it was a bad switch or bad contact. Two weeks later, same problem, replace brake switch with a new one, no difference, still not working. In the process of changing the switch one of the power wires to the switch broke. Repaired wire, can start vehicle again, everything else not working as described above. Have checked fuses and bulbs. Looks good. 4 way flashers work. Tested the steering wheel in several positions, does not seem to make a difference.

 

Have you checked the ground for all the lights .
it's on the frame by the spare

 

I'll have a look.

 

Thank you. Everything looks good back there, but after fiddling with the wiring everything seems to be working again. I do recall that we fiddled around in the back there the first time too, and everything worked after that as well. I did not find the break or loose connection but pretty sure the problem is in the back end wiring somewhere. We are too cold to be pulling on wires outdoors right now, so we'll tackle this when it warms up.

 

the wire may not be broken.. it may be corroded or the grounded attachment rusted which is changing the resistance in the system.

 

Thanks Steve, I found one of the wires that goes to the licence plate light bulb was broken off and exposed wire dangling against the frame. I removed it. Don't know if that was the issue but will run for a while and see what happens, it was working today. If problems persist, I will go after that ground wire. Seem well secured but it was packed in moist dirt which could cause corrosion as you say.