There is a site at
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that has the information you seek. While it's not free, the cost for the information is more than worth what you will get out of it. I used it to fix my blank display problem and was very pleased with the detailed instructions (lots of step by step pictures) and there are a lot of explanations as to what can cause the problems on these radios (it's not always one thing). I believe you can request the schematics (as they are not posted in the web site, but I talked to others before I bought into the web site that were listed as "success" customers on the web site that requested the schematics and got them with no problem). I know it's easy to get spoiled by free information on the Internet, but I found this web site information was well worth the cost. My wife wonders why I went 8 months with a blank display!?!