Take the voltage of the LED and subtract that from 12V. Then divide that by the forward current rating of the LED. That gives you the resistor required.
E.g. for a 2V LED with forward current of 20mA, the required resistance is (12-2)/0.02 = 500ohm.
'93 16V Mondeo saloon
Full factory RS setup lowered on 17s
K+N 57i, splitfire leads, chipped, full aluminised twin-exit exhaust
Sounds by Alpine, Infinity, Vibe, JBL
First Mondeo with indiglo gauges
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