brake lights are out.... help

richabilly · Post by **richabilly** » November 19, 2009, 6:29 pm

searched for this but didnt find anything. A friend noticed my brake lights are out. Running lights work, turn signals work, hazzards work, but no brake lights.

at first i thought fuse -- but all the other things work and i didnt think the brake lights would have their own fuse. Besides, i have NO clue where the fuses are on my 61 uni -- anyone help on that one?

My second guess is the brake pressure switch on the master cylinder. does that sound likely? Or do you think it is something else. I am a novice wrench, but this seems like something i can handle and i want to work on my own truck as much as possible anyway.

Thank you!

Obsa · Post by **Obsa** » November 19, 2009, 6:52 pm

Since the pressure switch just completes the circuit for the brakes you can check it by removing the wires from the switch and use a jumper to connect them if the brake lights come on then you have a bad pressure switch.

ICEMAN6166 · Post by **ICEMAN6166** » November 19, 2009, 7:03 pm

Obsa wrote:Since the pressure switch just completes the circuit for the brakes you can check it by removing the wires from the switch and use a jumper to connect them if the brake lights come on then you have a bad pressure switch.

key must be in on position for this test to work

the fuses for 61 are on the bottom of the headlight switch

Obsa · Post by **Obsa** » November 19, 2009, 7:36 pm

Thanks Ice, I forgot that detail that darn CRS again

Ford blue blood · Post by **Ford blue blood** » November 19, 2009, 9:38 pm

The brake light circuit should have power all the time. There is a 15 amp fuse that powers the parking lights, plate light and the brake circuit. Check your park lights and jumper the brake switch if there are park lights (fuse is good).

ICEMAN6166 · Post by **ICEMAN6166** » November 19, 2009, 9:53 pm

the early trucks had to have the key on to make the brake lights work. not sure when that changed.

none of mine work without the key being on.

blackagatha · Post by **blackagatha** » November 19, 2009, 10:58 pm

ICEMAN6166 wrote:the early trucks had to have the key on to make the brake lights work. not sure when that changed.

none of mine work without the key being on.

That's strange.... Personally, I would re-wire that so they will work any time...

Post by **Casey 65** » November 19, 2009, 11:24 pm

my '65 has two terminals on the master cylinder that have to be cleaned with steel wool every so often.

Ford blue blood · Post by **Ford blue blood** » November 20, 2009, 8:42 am

ICEMAN6166 wrote:the early trucks had to have the key on to make the brake lights work. not sure when that changed.

none of mine work without the key being on.

Mine is a 61 and bone stock. The 48 I had was just a bare cab when it came home so don't know about it. The 73 brakes were hot all the time and the 93 brakes are hot all the time.

rayford · Post by **rayford** » November 20, 2009, 9:37 am

i had the same thing happen on my 65 it was a bad blinker switch

Gritsngumbo · Post by **Gritsngumbo** » November 20, 2009, 10:12 am

FYI: Here's a pic of the fuse box/headlight switch assembly.

I printed out a copy and put one in each glove box for reference.