I have an electric fan 12v which cools the ignition module on a falcon ED 4.1. Can anyone tell me which wire I can tap into so that I only get 12v when the motor is running?

Thanks

To find the right wire, you can try checking the wires near the starter switch or fuse box. Use a multimeter to measure the voltage on these wires when the engine is running and choose a wire with a voltage of 12V.