Dimmer switch

You know that dimmer switch that we have when we the lights are on and if it's bright out you can brighten the lights inside the car? Well that switch is acting up for some reason. When I am driving and the lights are on the dimmer is of, but then I hit a bump or step on the brakes and the dimmer light turns on and the clock and middle gear light(nexyt to the speedo) light up. I'm not sure how to diag it, but it's too annoying at night to drive like that and a pain to keep turning it off, and sometimes I can't turn it off the dimmer because the button doesn't work.

Anyone else seen this before?