COOLING FAN CONTROL
EC-1097
< FUNCTION DIAGNOSIS >[K9K]
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COOLING FAN CONTROL
System DescriptionINFOID:0000000001162544
The cooling fan motor is controlled by the ECM.
COOLING FAN OPERATION WITH THE ENGINE RUNNING
Cooling fan operate is guaranteed by a 2-speed fan assembly (LOW speed and HIGH speed).The ECM
requests the IPDM E/R to actuate them via the can communication. To provide cooling:
Engine running
- LOW speed is actuated when the engine coolant temperature exceeds 96 °C (205°F) and is deactivated
when it drops below 94 °C (201°F).
- HIGH speed is actuated when the engine coolant temperature exceeds 104 °C (219°F) and is deactivated
when it drops below 102 °C (216°F).
If the engine coolant temperature exceeds the threshold of 115°C (239°F), the ECM requests the IPDM E/R,
via the CAN communication, to switch off the air conditioning compressor so as to reduce the load on the
engine and attempt to limit the rise in temperature. The cut-off request is cancelled if the engine coolant tem-
perature drops below 110°C (230°F).
If a malfunction in the engine coolant temperature sensor circuit is detected, the ECM requests that HIGH
speed operation.
In addition to engine management, the ECM centralises the cooling requirements for the climate control and
automatic transmission/sequential gearbox functions (where fitted).