Brake lights not working when running or head lights are turned on.

toma65

I have a 2000 jeep Cherokee, when I turn on the running or head lights the brake lights don't work, except for the courtesy brake light it always works. The brake lights work fine with the running and head lights off? The police didn't like that. the bulbs are ok and no bad fuses. I'm stumped.

elias

consistent with relay failure. brake light relay or turn signal relay.