dimming headlights/brights don't work

i recently bought a 98 ford explorer, everything works fine except for my headlights, when i turn the car on, the lights turn on to the parking lights and then after 5 to 10 minutes the brights come on, and they flicker for about 15 seconds before returning to my normal nighttime driving lights, i tried turning my brights on but they only work when i pull the handle towards me...i've browsed through some posts that had headlight problems but i wasn't sure if it was the same problem that i had, if anyone has answers please respond thank you!

Probably your multi function switch.