ELECTRICAL FAN CONTROL OPERATION
BHE014000140T47
• When the operation conditions are met for each function, the PCM sends an operation signal to cooling fan relay No.1 or No.2/No.3 to operate the cooling fan motors.
• The rotation speed of the cooling fan motor is switched between two levels according to a combination of the cooling fan relays.
• When only cooling fan relay No.1 is on, the rotation speed is low and when in addition to No.1, No.2 and No.3 are on, rotation speed is high.
Operation Conditions
|
Function
|
Operation condition
|
Cooling fan motor
|
Cooling fan relay
|
|
No.1
|
No.2
|
No.1
|
No.2/No.3
|
|
Regular-driving cooling
|
ECT: Less than 97°C {206.6°F}
|
Stop
|
OFF
|
OFF
|
|
ECT: 97°C {206.6°F} or more
|
Low speed rotation
|
ON
|
OFF
|
|
• When all the following conditions are met:
-
– ECT: 97°C {206.6°F} or more
-
– During fuel cut at deceleration
|
Low speed rotation
|
ON
|
OFF
|
|
A/C amplifier (A/C switch): ON
|
Low speed rotation
|
ON
|
OFF
|
|
ECT: 101°C {213.8°F} or more
|
High speed rotation
|
ON
|
|
• When all the following conditions are met:
-
– ECT: 101°C {213.8°F} or less
-
– A/C amplifier (A/C switch): ON
-
– Refrigerant pressure switch (medium-pressure switch): ON
|
High speed rotation
|
ON
|
|
After-cooling
|
• When all the following conditions are met:
-
– Ignition switch: OFF
-
– Drive-by-wire relay: OFF
-
– Metering oil pump: Other than during ignition switch off mode
-
– Engine compartment temperature high.
|
High speed rotation
|
ON
|
|
• When all the following conditions are met:
-
– Ignition switch: OFF
-
– Drive-by-wire relay: OFF
-
– Metering oil pump: Other than during ignition switch off mode
-
– ECT: 110°C {230°F} or more
|
High speed rotation
|
ON
|
|
Forced drive
|
During test mode (during test mode with WDS) when the AP is depressed.
|
High speed rotation
|
ON
|
|
Fail safe
|
When a failure occurs in the ECT sensor.
|
High speed rotation
|
ON
|
|
1
|
B+
|
|
2
|
Main relay
|
|
3
|
Cooling fan relay No1.
|
|
4
|
Cooling fan relay No.2
|
|
5
|
Cooling fan relay No.3
|
|
6
|
Cooling fan motor No1.
|
|
7
|
Cooling fan motor No.2
|
|
8
|
To PCM
|