lihinian wrote:jamesp15 wrote:Dual color LED, probably Red and Green, with a (probably) common cathode setup if that middle pin goes to a ground/-(negative) connection.
Should be able to trace it all out with a Multimeter in continuity or ohms mode.
Cool, now I can work this out hopefully. Is this what I'm looking for? https://www.ebay.ca/itm/20pcs-5mm-Dual-Bi-Col … 2wAAOSwjk9ZWpKW
If that center pin on the circuit board does go to a ground/-/negative, then the LED you linked to should work in its place. With it being chained to another pin I assume it is but all I can do is assume on that part. If that center pin goes to a +/positive voltage you would need a Common Anode LED.
Voltmeter set to Ohms or Continuity to with one probe held onto that (middle of the 3) pin and another held onto a _known_ ground (the metal around a screw hole is a good place, exposed metal parts like a back panel jack housing is usually another, or the negative pin on the battery) would tell you, if it beeps in continuity or if you get a low ohms reading its ground/cathode so it would be a Common Cathode. Can also try between the other 2 pins and a known ground, should get a really high ohms reading OR no reading at all if its a Common Cathode.
If the reverse of the above paragraph is true, then its a Common Anode LED. (as in if the middle pin shows no or really high ohms to ground and the other 2 pins show low ohms/beep on continuity it is a Common Anode)
Depending on multimeter, the Ohms setting might be more useful, the Continuity setting on some multimeters has a too low threshold to "beep" on some circuit layouts (for example might only been under 1 ohm or such when, when 10 ohms or such would still be OK as a circuit.)
I cant say for sure what would constitute a "low" ohms reading there might be (should be) a current limiting resistor in series with the LED, and could well be other circuitry and even the length of the motherboard traces make it so its not a "fixed" number I could give. Your looking for the pin with the lowest resistance to ground of the 3 if its Common Cathode (or the 2 with the lowest to ground if its Common Anode)
Hope that is not confusing or insulting, I am not sure of your level of comfort with a multimeter/etc.