ELECTRICAL FAN CONTROL [SKYACTIV-D 1.5]
id0140z5205000
Outline
• Through cooling of the radiator and condenser by operation of the cooling fan according to vehicle conditions, engine reliability and cooling performance have been improved.
• The PCM determines the engine operation conditions based on the signal from each sensor and performs duty-control of the fan control module to control the rotation speed of the cooling fan motor.
Block Diagram
Operation
Engine coolant temperature conditions
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• Output duty ratio is controlled according to the engine coolant temperature as indicated in the graph.
• While the engine coolant temperature is decreasing, it is controlled at a different temperature from that of when the engine coolant temperature is increasing.
A/C conditions
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• Output duty ratio is controlled according to the refrigerant pressure when the A/C switch is on.
Exhaust air temperature condition
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• If all of the following conditions are met to suppress temperature increase inside the engine compartment, the output duty is controlled at a ratio of 75%.
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― Exhaust gas temperature sensor No.3: 400 °C {221 °F} or more
― Vehicle speed: 40 km/h {25 mph} or less
After cooling control
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• To suppress temperature increase inside the engine compartment, the cooling fan operates (output duty ratio: 50 %) for up to 9 min under the following condition.
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― Exhaust gas temperature sensor No.3: 400 °C {221 °F} or more
Condition during collision
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• If a collision signal from the SAS control module is received, the PCM stops the engine cooling fan to avoid use of battery voltage.
