1.Testing tool: Multimeter
Select your multimeter to Diode grade.
(Remark:Maybe your multimeter different from Image XBS02,but just adjust it until show the Diode grade mark )
2.Important!!! To avoid short circuit,If you have turned on your amplifier,please wait 20minute before your Testing!
Because there is some electricity still stay in the power supply.They should be released in 15-20mins at least.