Ok ya i see where the red blue etc edge connectors are the numbers..i might not be puttn the probes on the u52 right thenGoogle "JAMMA pinout" and you'll have the connector pin numbers.
As for putting it right on a pin on U52 you'd need to put it on the right pin and it might not beep because of the 33 ohm resistor in the circuit. It depends on your multimeter and what resistance it stops beeping at.
Man i must be stupid im lookn on the site theres so many things that say u52 on there im still learning noob as hell at this..i fixed a ki2 missing chips before the lil smd chips were missing and the sound didnt work but bought some and sodderd it on and got volume back.. ok on the site theres so many part numbers names? Idk where the one i need is