Are you entering it correctly?
I used to have a Clarion, and if I'm coorect it used to have buttons 1,2,3,4,5. on the bottom, to choose stations for each bandwidth.
When reconnecting (if code was e.g.2523) you had to press those button in order - NOT button 1 twice, button 2 five times, button 3 twice and button4 three times.
So for 2523 press 2 once, 5 once, 2 once and 3 once, and it should kick into life on the last digit.
If the screen is not already dimly lit it may not be connected correctly.
Steve, February 2007