Audio Systems: harmon kardon receiver bmw 1998, harmon kardon receiver, automatic brightness control

Question
I have a 1998 bmw with a harmon kardon receiver.  The display only lights if the sun hits it directly thru the sunroof.  I suspect it has some sort of automatic brightness control.  Can this be adjusted or replaced to illuminate the display in low light conditions?  thanks for your help.

Answer
What does it do if you turn on the headlights? The dash light dimmer control should be the only other thing controlling brightness then. If it still acts the same way, the radio would have to be sent in for repair, or replaced with an after market CD player.