I have a Pioneer DEH-P47DH in a '01 Silverado. It suddenly has decided to do nothing - no on/off, inputs do nothing. Radio doesn't turn on. However, it will play a CD when inserted, and the volume control works. The clock works. To turn CD off, I have to eject. No other controls are active when CD is playing. The CD just plays from beginning to end. When I eject CD, the unit just shows the clock and is lit up.
One day, the problem went away for a short trip. Then, it came back and is unresponsive. Any guesses - is the problem in external wiring or in the unit?