I've had a Mk6 for 3 years and it's now clocked around 105k miles. I've had a lot of work done on it including new head gasket, belts, water pump and brake lines to name a few. On a recent drive up to a viewpoint I noticed the coolant boiling over. On inspection the radiator fan never came on. To diagnose this I've changed the fan relay so far. If I apply power directly to the fan, the fan spins. I know the temperature sensor is on the head and it is working as the hidden menu tells me the exact temperature on the dash. Before replacing the ECU does anyone know of anything else I could try? All I can think of is DW40 on connections. Has anyone had anything similar?