I’m stuck and could use some help, Beomaster 6000 won’t start up. Some LED segments light when connected to mains power but nothing more. No relay action, nothing. Everything I test looks normal now. It seems like it won’t reset and go into standby.

Background: I rebuilt the amp and pre-amp years ago, sent it off with a friend who has used it nearly daily for about 4 years. No problems, until it would start for him.

What I know: I have a known working Beomaster 6000 that I removed the front panel, (boards 2,3,4,5) and connected to the faulty Beomaster. Works fine. So I can eliminate any problems up stream. Problem follows with board 2 when swapped.

5v to board 2 is intact. Unable to calibrate the reset according to the manual, R89 pot was bad, replaced it, then I was able to calibrate appropriately with the scope. The 2 original electrolytic caps on board 2 tested as good, replaced with new.

4.9V on processor pin 39.

Swapped processor with the known good processor from the working Beomaster. No change and the processor from the faulty Beomaster works in the good Beomaster so I can eliminate the processor. Tested D6, TR 5,6, 27, 28. All voltages as excepted and test as working out of the unit according to my PEAK component tester. Shorted R90 to manually reset several times. Reflowed solder on all connections a couple times. Replaced 40pin processor socket.

Nothing.

I grabbed a parts unit Beomaster 6000, that too has the same problem of not going into standby, tested and shows a good processor. Haven’t spent much time with that unit.

So, I have 2 Beomaster 6000s with the same problem on board 2 and a known good Beomaster to compare to.

Every voltage point I see on the service manual I test as appropriate so I can’t pin point where the fault is and could use any help thinking this through.