System Description
System Diagram
NOTE:
Both "Engine coolant temperature sensor" and "Engine coolant temperature sensor 1" are used in this information. These indicate the same part.
INPUT/OUTPUT SIGNAL CHART
| Sensor | Input signal to ECM | ECM function | Actuator |
|---|---|---|---|
| Crankshaft position sensor | Engine speed * 1 | Cooling fan speed request signal * 2 | IPDM E/R ↓ Electrically-controlled cooling fan coupling |
| Camshaft position sensor | Camshaft position | ||
| Engine coolant temperature sensor 1 | Engine coolant temperature | ||
| Refrigerant pressure sensor | Refrigerant pressure | ||
| Intake air temperature sensor | Intake air temperature | ||
| Battery | Battery voltage | ||
| Combination meter | Vehicle speed signal * 2 | ||
| BCM | A/C switch signal * 2 | ||
| Cooling fan speed sensor | Cooling fan speed |
* 1: The ECM determines the engine speed by the signals of crankshaft position and camshaft position.
* 2: This signal is sent to ECM via the CAN communication line.
SYSTEM DESCRIPTION
- Based on a signal transmitted from each sensor, ECM calculates a target fan speed responsive to a driving condition. In addition, ECM calculates a fan pulley speed according to an engine speed and transmits a cooling fan request signal to IPDM E/R via the CAN communication line to satisfy the target fan speed. Then, IPDM E/R transmits ON/OFF pulse duty signal to electrically-controlled cooling fan coupling.
The cooling fan speed sensor detects a cooling fan speed and transmits the detection result to ECM.
- ECM judges the start signal state from the engine speed signal and battery voltage.