Hi

I have Bc9k, and it doesn´t do anything reasonalbe. It seem to have all voltages it should have, but when plugget in mains, nothing happens, only clikc from relay, no lights, no reaction to anything. 

Then if reset wire from amp board to cpu is removed (to float), there is some attempt to reset, but result is random lights on, nothing else. If reset is connected, all functions dissapears (like reset line were active). Line is low, but all voltages before it in circuit are present. Should it be high? If so, I cant see why it isn´t.

I do not have service manual for 9k, only for 9500, is it useful, specially on cpu part and measurements?

Maybe you allready know this, but just to be sure: First of all take off the glass panels of your BeoCenter 9000 before you open it! A lot of glass panels have broken in the past because they were loose and fell off while the BeoCenter was in service-position! Also check the plastic hinge on which the metal rod is mounted with which you can put the BeoCenter in service position. The plastic may break because of age i which case the top of the BeoCenter will drop to the front which might damage it. I always let the top part rest against something when it is open to prevent this from happening.

And then your main problem. I have had the same problem with several BeoCenters. It could be the processor but it could also be bad solderings in the powersupply. Take out the powersupply which is located behind the CD-player (the board with the big capacitors) and resolder it. That might do the trick! Let us know if it solved the problem!

Regarding the service manual, BeoCenter 9000 is practically the same as BeoCenter 9500, the biggest differences are the microprocessor, the IR transceiver and the input-select.

Yes, they (panels) are allready out of glueing, so no problem. There was one wisible bad solderring, on C17 ground side. And, no, resoldering whole board did not help. Reset line stays low (I did confirm that it should be high) P85 pin 8. Line between TR13 and TR15 is 5V as should, also there is 5V present on P82. Any idea what should be on base of TR15? On base of TR16 seems to be 0V but on C of TR16 is not 5V as should. BTW all of this is from BC9k5 manual.

Ha, found it! Extermely small crack on relayboard 66! Now have to put all together again and see if it still works.

BTW, when inspecting this aparat, I noticed some traces of shortcircuit between transformer secondary botton wire and sidewall of machine. Could be good idea to put some isolation board there.

You could also use some heatshrink around the wire to isolate it.

Relayboard 66 is only for switching on the CD-player, so this might not have been the cause of the problem. But please let us know if the problem is solved!

Really? CD only? I dont have BC9k servicemanual, and in BC9k5 manual has different kind of relay, so I dont know if circuity differs and how much. Maybe it was then something like bad connection somewhere? Anyway BC is now operational.

Yes heatshink is one solution, but it needs to lift transformer out. In this case there was some extra isolationtube(dont know exact name in english, but its brown and fabric) on wire. Anyway I think that board is easy to slip there.