i need help with brake lights

[fnelson71]

ok i bought a shuttle bus 24'. 2001 E450 16' behind the driver seat i went across some railroad track my wife said i had brake lights before i went over the tracks but now i dont have brake lights


here is a twist i have brake lights if the key is as soon as i turn on the key the lights dont work i have checked the ground and its good.

[claydbal]

run a jumper to the positive side of the brake light switch and to a "hot" wire and see if ya get lights. that will show if the circuit from switch to lights is good.

[fnelson71]

the switch is good the brake lights work when the key is turned off. as soon as you turn on the key the brake lights stop working and im getting power out of the switch when key is on. i ran a ground wire to the lights so its not a grounding probelm.

[claydbal]

so, power from switch when key is off, and power from switch when key is on??? whats da difference?

[fnelson71]

The brakes don't work. Until you turn the key off. It must be interlocked with something

[fnelson71]

I jumped the switch same thing no brake lights when the key is on but as soon as you turn it off I got brake lights

[claydbal]

i would look for a 5 prong relay somewhere in the circuit between the brakelight switch and lights. they can be wired (rewired) to switch off a circuit when power is applied, or switch on a circuit when power applied. only explanation (WAG) i can come up with???????