Trouble identifying part

[Gryphon327]

Hello,
I'm having some trouble identifying a part taken from an old Sega Genesis. I thought it was a transistor, but now am having doubts. What I have is a small black square (8mm wide, by 7mm tall) with 3 pins. Both sides are flat and it is about 2mm thick. There were lots on the board and most of them were connected to the controller inputs. The only markings on them are 222 or 271 (just realized that there were 2 different types). When tested for continuity the 2 outside pins show continuity in either direction. The center pin does not show continuity with either outside pin in any direction. I have 18 of the 222s and 2 of the 271s. I'd be willing to sacrifice a few 222s if there is some test that would help with identification.
Thank you,
Gryphon327

 

[Ian]

Any chance you can take a picture of what one of these looks like and upload it to the site? That should help identify the device, along with your description

 

[55pilot]

They are "T" type EMI filters on the I/O lines. The 222 have a 2200pF capacitor while the 271 have a 270 ohm capacitor.

Why do you believe there is a problem with these parts?

---55p

 

[Gryphon327]

I don't know if there is a problem with them, I just didn't get the expected results when I tried to test them. I thought they were transistors at first. Thank you for the identification. Now I know what to look for to find the datasheet.
Thank you,
Gryphon327