Radio Interference From LED Lights

[clewis]

Late, but a suggestion that will help in more stubborn situations: if you can open up the housing and you can identify the power regulator block (between the LED itself and the power supply line), put the aforementioned .1uFd capacitor across the pair of input wires, and another across the output pair, both as close as you can get it to the regulator block. If your skills extend to vampire tapping wires, use it. Keep the capacitor leads as short as reasonably practical.

The noise is generated in the regulator, not the LED element itself. Keep the paths thru the capacitors from/to the regulator as short as reasonably practical.

The capacitor on the input line suppresses ring back through the electrical system of the tractor. The capacitor on the output side suppresses radiated noise.