# Denon AVR-900



## popeyebud (Sep 22, 2012)

*Dead unit*

Hello,
I am looking for help with my Denon AVR 900, The unit has no power, all fuses are good All Audio outputs are fine, No burnt components Or Burnt smell. I am wondering if anyone knows of Voltage test points.It kinda looks like it may be in the standby power. It looks like it is a power supply problem of some kind. Thank you for any kind of help. bud


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## octaneman (May 13, 2009)

Hi popeyebud

You'll need to check the power mosfet and the opto-coupler if they are switching the transformer on.


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## miyagi2 (Jan 8, 2012)

look in the power supply for a two legged transitor, might be marked as an ic (What ir really is is a quick blow fuse) Have different model denonm mine was marked ic502. Good luck


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## popeyebud (Sep 22, 2012)

Hello octaneman and miyagi2,
Thank you both for your Ideas, After rechecking everything you suggested everything looked ok, However I did find that the mainpower relay driver transistor was burnt and destroyed.
I have been looking for open resistors or shorted diodes but everything has checked good. I don't know if either of you has access to the denon AVR-900 schematic but I have almost run out of ideas.
Thank you again for any help you suggest.
popeyebud


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