To access the "brains" of the Z906, you must remove the back plate of the subwoofer.
If you are using a multimeter to diagnose the board, look for these verified voltages: logitech z906 service manual fixed verified
You will see two main sections: the Power Supply (top) and the Class D Amplifier board (bottom). 3. Verified Voltage Reference Points To access the "brains" of the Z906, you
+5V (Necessary for the console to wake the system). logitech z906 service manual fixed verified
Use a Philips head screwdriver to remove the perimeter screws on the back of the sub.