I have a park brake light staying on with the keys out of the ignition, and killing my battery, fluid is good, tried unplugging the switch, and still it stays on. Had to disconnect battery for the night so it will start in morning. Anyone ever hear or know how to fix this?
Thank you

 

The switch may "fail on" such that when you pulled the plug it stays on. I don't know for certain but a little detective work with a multi-meter would probably confirm this. I can't really believe that this particular circuit is all that complicated. 12V, a ground, and a position switch. A HAynes manual should have the wiring diagram. I may run down and take a look here in a few minutes.

 

I took a quick look at the wiring diagram in the Haynes manual which covers 91-99. Mine is a 96 and I do not have a separate light for the parking brake. I have a Sport with a 5 spd. and ABS. It uses the "Brake Light" for the parking brake and the brake level warning switch. I have never looked at the actual switch but looking at the wiring diagram, both the level switch and the parking brake switch appear to work by establishing a ground when the switch is closed which causes the indicator light to come on. When the switch is open, the ground connection is broken and the light stays off. Nothing real fancy there.

I really doubt that the problm is with either switch since the indicator bulb is not supposed to get 12V unless the ignition swithc either in the Run or Start position. A bad swithc might cuse the light to stay on when the ignition was on but otherwise it would go off.

I looked at your profile and see that you are in Canada. I believe that you folks have daytime running lights up there as standard or mandatory equipment. If this is correct, Ford inserted the daytime running light module between the parking brake switch and the brake indicator light, upstream of the splice for the brake level switch. This may well be the source of your problem. Wish I could tell you more like where the daytime running light module is located but I've never seen one down here in Texas. Hope this was of some help.

Another possibility is your igition swithc is bad and you are somhow juicing the circuit even though the swithc is off. Problem with this is that the switch should go off if you do not set the parking brake.

BTW, I am assuimng that you pulled the switch for the parking brake. Also, I am assuming that you checked to see if the light goes off with the ignition off if you release the parking brake.

 

Took daytime running light module out about 2 years ago, haven't had any issues with that. Disconnected battery for the night, reconnected this morning and park brake light is now out. I am periodically checking my battery voltage throughout the day to see if it is dropping. Other than that I don't really know what else to do...

 

We got her figured out. Pulled the fuse for the fog lights and everything is now good. The fog light and daytime running lights are apparantly on the same circuit. The winter crap got into the DRL wiring harness and shorted out causing my park brake light to stay on all the time. So we pulled the fog light fuse (truck doesn't have fog lights anyway) and all is good.

 

Glad to hear you found a resolution.