The illumination in my 2004 Honda Accord stero and heat control dose'nt illuminate.

The failure of the illumination to only the stereo and heat control panel can be due to possible few reasons which you can check.
1. It can be due to failure of the connectors of the wiring harness to the stereo or panel. Use a multimeter to check the +B( 12V) as the park lamp is switched on. If absent there can be fault in the harness or the connectors.
2. Failure of the lamps in the panel- the LED's could have lost connection or failed. the Panel lamp could have failed in the holder or the lamp.
3. Finally there can be a faulty ground connection to the stereo or panel. tap to see if the lights come on.