I have my dash apart and cluster out doing the factory tach swap. Noticed the bulb was missing from the brake warning light. replaced it and now it is illuminated all the time - even when the ignition is off. Any ideas?

 

I assume that you are referencing the parking brake light? I'd check your actual brake switch before I worried too much. Also how sure are you that said wire goes there?

 

My guess is you're talking about the light that indicates a pressure difference between the front and rear system. Make certain front and rear brake systems are working right and reset the sensor.

 

Silly question. What year truck, and what year cluster? Both printed circuit board the same color?

 

It should not be lit with the ignition off, unless it is shorted to ground or there is a problem with the ignition switch.

 

82 F150 C6/300 I6: looking at the Haynes wiring diagram I looks like the circut goes thru the brake light swtich in between the ignition. The brakes lights work fine. I have noticed the ignition switch is worn causing the accessories to cut off at times. have to wiggle the ignition to get them back on. Was planning on replacing the ignition switch for that...maybe it will fix both.

 

It most likely will fix both.

Your brake lights in the rear of the truck do not go through the ignition switch, but the Brake warning light in the dash does.

 

if the ignition switch does not fix it...is there a switch of some sort on the emergency brake? Could be the actual brake light switch also

 

Not on the 1982 no.

First year of Combination Parking Brake light, and Brake Failure warning light is 1984.

Even then it would not stay lit with the ignition off.

The brake light switch on the pedal is hooked only to the rear brake lights. It's not hooked to the Brake Warning lamp in the dash. The Brake warning lamp is hooked to the porpotioning valve switch in the engine compartment, and the ignition switch.

Even if there is a problem with the porportioning valve, or porpotioning valve switch, it would not stay lit with the ignition off...

 

good deal. will put an ignition switch in this week end.