My car radio display light does not turn on most of the time. What's the cause? on 1999 Nissan Altima

When I start the car only in very few occasions the display light turns on(specially in cold weather) stays for few minutes. Then the light is gone and it stays dark all the time. However, the display shows the time, radio channels and tape modes. Since the light turns on, the display light bulb is not fused. So my question is how to fix the problem? Is it the problem with one of the connections in the harness ? Thanks

Asked by for the 1999 Nissan Altima
Your problem is in the radio itself, take it to a radio repair shop or replace it.