2003 Buick Rendezvous Lighting problems

I have problems trying to get the dash lights increase in brightness using the variiable control on the interior during a normal daytime especially when I try to see the speedometer (due to the poor design of the dash which can block exterior light from illuminating the dial especially around 10:45 and 11:15 am mst.) Esp. When I'm driving

Tl* the contact owns a 2003 buick rendezvous. While the vehicle was parked, the horn activated independently. The failure persisted until the battery was disconnected. The failure occurred several times. The vehicle was not diagnosed or repaired. The manufacturer was notified of the failure. The approximate failure mileage was 93,000. Updated 11/20/14*lj updated 5/4/2015 *js

Dt*: the contact stated while driving 30 mph, all the interior lights went out intermittently. The vehicle was taken to a service dealer, where the dealer was unable to determine the cause of the problem. The consumer stated the service engine light stayed on for days. The alrm didn't work, the key would get stuck in the ignition, the ac did not cool properly, the abs would engage when it was not needed, the battery was replaced, the turn signals wouldn't cancel, the doors wouldn't unlock when the vehicle was placed in park. Updated 12/29/06. *Jb

The vehicle started blowing fuse and the headlights came on and off without prior warning. *Ak