System Description
ECM controls cooling fan speed corresponding to vehicle speed, engine coolant temperature, refrigerant pressure, air conditioner ON signal. Then control system has 4 -step control [HIGH/MIDDLE/LOW/OFF].
Cooling Fan Operation
Cooling Fan Relay Operation
The ECM controls cooling fan relays through CAN communication line.
|
Cooling fan speed |
Cooling fan relay |
||
|
1 |
2 |
3 |
|
|
Stop (OFF) |
OFF |
OFF |
OFF |
|
Low (LOW) |
ON |
OFF |
OFF |
|
Middle (MID) |
OFF |
ON |
OFF |
|
High (HI) |
OFF |
ON |
ON |