Testing for failure with a multimeter is only partially effective, whereas a dedicated optocoupler testing circuit provides ...
So a few months ago, I stumbled upon a thing at Adafruit.com called a "Charger Doctor" which was really just a Multimeter designed to slip inline with your USB cable. It was $7.50 and I liked it.
Results that may be inaccessible to you are currently showing.
Hide inaccessible results