When parking lights are on, brake lights on also, or when I brake the parking lights, dash lights ,etc are activated. Turning on signal indicator, dash lights, etc also flash. Replaced headlight switch, no change. Wired light grounds directly to bat neg, no change. Disconnected dimmer switch, no change. Any help would be appreciated. BTW called Ford svc dept, explained problem was told the mech's had no idea what problem was.

 

You have a shorted bulb, replace it in one of the tail lights.

 

Thanks. Replaced the bulbs (3157's), but still a nogo. Started raining, so will have to wait to try something else.

 

Im thinking you have a wire somewhere in the harness that is stripped making contact with each other thats why both are on with running lights and both light up when you apply brakes. check where they go through holes that could of chamfed them. Other than that I dont know.

 

at some point in it's life, someone has hooked up trailer lights. they have shorted out, because they are corroded. look under the bumper, and in that area, any wireing that is not factory, remove it, and your problem is solved. I have run into this so many times, as soon as someone says the dash lights come on when I brake, that's the first place I look

 

Thanks for the good suggestions. As dustybumpers said someone had added a trailer pigtail, disconnected it, problem solved. Two of the wires had gotten crossed, bad insulation.

 

great to know it is fixed, and diddn't cost a whole bunch of money