ELECTRICAL FAN CONTROL OPERATION
id014000104000
• 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
|