Have lost the lighting on OEM radio GM #25799567. All functions are working, including XM, but unable to determine stations, and no time indicated. Pulled radio, and monitored the illumination voltage on connector X1, pin 7, and voltage is normal with the ability to vary with the dimmer switch. Took radio apart, and no apparent trouble noted. Looks like my options are repair, or replacement. Any suggestions on reliable replacement vendors, or repair service?

 

Found a radio at www.replacementradios.com. and replaced it. Company was easy to deal with, I had to copy the vehicle's code sticker on my glove box cover, and send it to them so they could program the replacement radio, It had to be right since I had XM, which is a separate receiver mounted behind the glove box. It was basically plug and play with no trouble.
The replacement radio was a different model number, but compatible with mine. It was a new radio that was termed a "new takeout", and was $179.95. It cost $50 to have it programmed, and has a 6 month warranty. The cheapest dealer price locally for reprogramming was $100. Perhaps this info will help others.