LED Won't Light? Troubleshooter
Most dead LEDs are in backwards.
LEDs only work one way round. Work through one question at a time. You can go back or start over whenever you like.
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Safety: this troubleshooter is general information for low-voltage DC learning circuits. 240V AC mains can kill: in Australia, work on mains wiring must be done by a licensed electrician. Disconnect power before you touch wiring.
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