Brake lights are staying on

[Lindsaym151]

1St , let me say i have searched this ,googled it,and prayed for the problem to fix it self.That said, I noticed today when i changed my rear light bulbs ( the large 2 filiment ones at the rear of the truck ,both filiments where glowing at the same time.
I have a new air acuated brake light switch, i have jumped the 2 brake light wires and that works,I have set the 3 position light switch to both parking and service positions.
What am i missing here? New switch bad? not enough air pressure? mine runs at 30 -40 psi all the time. I checked for air leaks -NONE (Checked with soap and water
Any suggestions would be greatly appreciated
Thank you in advance

 

[doghead]

What runs at 30-40 psi? Your truck should hold 90-100 psi all the time.

Do the lights go out with the 3 lever light switch off?

Do they come on correctly , with the brake pedal?

Try measuring your brake light switch with nothing connected and measure the resistance between the two terminals. Should have almost 0 ohms when brakes are pressed, and go "open" when the pedal is released.

 

[Danl]

Danl M915A1

Do you have a lever on the right hand side of the steering wheel that is used for tailer towing or air tailer breaks, if you do if the lever is not all the way up your break lights will stay on check the lever frist , I think you will find it pulled down a little .

 

[Lindsaym151]

Hey dog head,
This truck has always only produced 30-40 psi (ON MY GUAGE) also yes lights do go out with the 3 lever switch in the off position.I will check ohms tomorrow!
It must be beautiful in Upstate NY right now. Originaly from northern VT

 

[Lindsaym151]

Hey Dani ,
No I dont have anything that looks like that!
Thank you though!

 

[doghead]

Does your low air buzzer operate? It should stay on until 60 psi is built up.

44 F this Am. The leaves are starting to change color and fall. The best is yet to come.

 

[eagle4g63]

I would definitely check the air pressure with a know good gauge..........doesn't even have to be mil spec just check to see you have enough air.

After that, like doghead said check the air switch to see that it is doing as it should........

You know, check to make sure there are no other bulbs doing weird things....leave off the lens and check each switch setting and make sure the right bulbs come on...........picked up a trailer last week and was told one of the brake light bulbs was out.....it was just a wire hooked up wrong and a different bulb was coming on.

 

[Lindsaym151]

Hey Eagle, LOve it when you chim in (Know im in good hands)I've checked everything!3 times,All functions are 100%.
Ive got a switch that is stuck open or closed,Both filiments are on at the same time! As if i have put a jumper wire between both leads to check a circuit.
Im not an electrical guy dont know how to trace it down.
Im going to wait till i can get (MY GUY 0 to look at it!

 

[G-Force]

Unplug your brake light switch. Your lights should go out. If they do you have a bad brake light switch.

 

[steelandcanvas]

Do you have a lever on the right hand side of the steering wheel that is used for tailer towing or air tailer breaks, if you do if the lever is not all the way up your break lights will stay on check the lever frist , I think you will find it pulled down a little .

He has a Deuce Cargo Truck, they don't have a "Johnny Bar".

 

[Lindsaym151]

Man i hate spending 45.00 plus shipping! and its BAD! WTF, am going to look for a NAPA clone!

 

[Lindsaym151]

Eagle, where do i check the A/P ? what section of pipe do i cut and install a guage?
Or am i not reading this write? I can't see anywhere i can install the guage that isnt high dollars?

 

[SoundGuy]

I would open the air hook up on the driver side for the trailer brakes and see if air is coming out. There is also a valve that would need to be opened. If everything is correct there should be no air when no brakes are not pressed. (This is only to test. Don't leave it like this.) Some switches don't require much air pressure at all to turn on. If air is leaking out, it could be the airpack or the brake pedal not adjusted properly.

 

[SoundGuy]

Eagle, where do i check the A/P ? what section of pipe do i cut and install a guage?
Or am i not reading this write? I can't see anywhere i can install the guage that isnt high dollars?

You could buy a air line that hooks up to the emergency glad hands (passenger side) from most truck stops and connect it there.

 

[Lindsaym151]

Ok heres a picture of my drivers side cockpit, This is my 1st deuce !Not sure how to track this down. I will take pics tomorrow of the air pack & master cylinder.
I hope they help us all.
P.S.
I had a guy help me put in the master cylinder.
When crawling under the truck today i noticed a spring not attached to any thing(where does that GO!)

 

[Lindsaym151]

Sorry got carryied away with the spring issue here are the pics

 

[SoundGuy]

On the rear of the truck there are glad hand hookups for the brakes. Pull the one off for on the drivers side. Also open the valve behind it. It should blow out air web the brakes are pressed only. Also there should be a spring on the brake petal to help it return.

 

[eagle4g63]

There is 2 ways to hook up other than the glad hands, you can just unhook the gauge and use the line that is there or you can take out one of the drain valves on the bottom of one of the air tanks, screw in a gauge into the hole in the tank itself.

As to the 2 filaments lighting they do on a deuce.....if you take out the large bulb you will see that there is only 1 point on the end of the bulb.......they use 2 filaments so as to make them 24 volt..........funny way to do it but if one filament was in there than only 12 volt.....2 filament in a series make it able to run on 24 volt.

What I was talking about is when you have someone push on the brakes.....does a different bulb light up? if so than a wire is hooked up wrong. They use a different bulb for each thing in the light housing, not like a civi truck where one bulb has 2 filaments and each does something different.

Did the lights ever work the right way? since you had it. If so.....than what changed since the last time they did? That is what I would look at as the problem.

 

[Lindsaym151]

That said wich bulb should be the brake light bulb? I noticed even the small bulbs have 2 filiments.
The more i learn the stupider i get!
I know your trying to help and I do apprecciate it, but man I hate electrical problems!

 

[Lindsaym151]

As far as knowing if I ever had brake lights,I don't know? I was told the other day they wern't working! News to me!I just thought I was surrounded by S#$%Y drivers!
OPPS my bad!