onkyo SR606 going into protection mode

Thread Starter


Joined Nov 13, 2015
I was wondering if anyone could help with a problem I have on my Onkyo 606. I have two of these one with a HDMI problem and one which is going into protection mode intermittently. I am trying to fix the intermittent protection one first. Sometimes it will run for 20 min playing music and some time it will go straight into protection mode. This happened even with all input and outputs disconnected.

I have checked all power transistors and found one channel open shorted. I have removed all the transistors from this channel, power up and still have same issue.

I decided to swap some cards with the other amp to eliminate them from the circuit. When placed the video PC board onto the amp without the protection fault with in 3 min of power up this amp went into protection. Now I am thinking this board may be causing the protection fault. I can see this has a power supply and feed the poff & poff2 plus other supplies to the main processor. Has anyone had this problem and is there something on this board that is worth me checking out first. I am thinking a capacitor problem or transistor on the power circuit causing this.