Hey guys, I have a Stern Star Trek Premium that had a CPU failure. Stern replaced it, but initially sent the wrong CPU which took a few days to figure out. Now, with the correct CPU all Row 3 switches are not working, even though no switch failures show in Diagnostics. Stern techs are really trying to help, so I appreciate that. They are asking me to take the CPU out and do some Diode tests on transistors Q2 and Q3. Anyone experience similar? I can do simple multi meter tests but I am not at all an Electrical Engineer. Any ideas or what to look for? The other switch Rows in the switch matrix seem fine during hand testing.
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