Brake warning light on 70 bump

[peanutman]

The brake warning light was on in my truck when i bought it. master cylinder is full front and back. Have a good full solid peddle. Everything seem to be working fine.
How do i check this out to see whats wrong or should i ignore the light. Still has manual brakes.

[kilog55]

i had the same problem/question here is what i found

http://www.fordification.com/forum/view ... ning+light

just need a better day and dry ground as i have no garage to do it.

[peanutman]

Would a bad switch cause the light to stay on or the fact that the light is on means the switch and system is working properly. And what kind of pressure drop would cause light to come on i.e. small leak or blown cylinder or line.

[kilog55]

leak, air in system??? <---not sure on the air part

i assume it is working properly but if the switch/wiring is bad it would never light up.

[Joshpow]

The light shows an imbalance between the front and rear brakes. If the switch has been tripped, it needs to be reset. It has to have a certain bleeding routine to reset, but I don't remember the exact steps. I don't know if this is the cae, but it is a thought.

[FORDification]

The thread kilog55 linked to above has the re-centering procedure outline, directly from the factory shop manual.

[sideoilerfe]

interesting. I've had 4 Bumps and NONE of the warning lights worked!!!

[FLATBEDFORD]

After going through the reset procedure about 10 times, I unplugged the darn thing.

[ezernut9mm]

i took the bulb out. immeadiately felt safer...