Engine Cooling Fan: Description

All 740, and 940 vehicles with are equipped with an electronic cooling fan. On 740 and 940 with LH 2.4 fuel system, fan is controlled by fuel system Electronic Control Unit (ECU) and pressure sensor in A/C system. On 740 and 940 with Regina fuel system, A/C pressure sensors control fan relay. Inside the coolant expansion tank is a thermal switch which closes at 239°F (115°C) and starts the fan to operate on full speed.