On most cars they have a button some where labeled clock, it's usually pretty darn small, but most times you just push that and the clock starts blinking and then you use the radio station buttons to change the time. That's what i've experienced in most cars.

Raymond

 

my father had the same problem in his 98 wagon...the clock on your car is with the radio right? you press some button which i cant remember(it may say clock on it or something) ...while holding that button down you use the radio tuning arrows(button on upper right) to set the hour/minutes....i cant remember exactly how it works but ill check for you tomorrow morning