That thing works with a Wiegand protocol.
Two data lines, one for zeros, one for ones..
Hookup power, connect two channel scope to DATA0/DATA1 and bring the card close.. If it works, it will read the card and send a burst of impulses on on both outputs..
That is not comprehensive test, but if that works it is very probable it is OK..
To be really sure, you would need to connect it to something that would decode full protocol and show you card data...