LEDs need complex wiring sometimes. This is how to test them.
Steps
1. Find the positive lead on the LED. This will be the long one.
- You can remember this by positive having more (the positive lead has more length) and the negative having less (the negative lead has less length).
2. Put the battery in between the leads through a resistor.
- If you are unsure of the LED specs, you are always safe with a 390 Ohm.
Things You’ll Need
- LEDs
- A button cell battery
Source : http://www.wikihow.com
