System Description
SYSTEM DIAGRAM
| Component parts | Function |
|---|---|
| Crankshaft position sensor | Crankshaft position sensor |
| Mass Air Flow Sensor (With Intake Air Temperature Sensor 1) | Mass Air Flow Sensor (With Intake Air Temperature Sensor 1) |
| Engine Coolant Temperature Sensor 1 | Engine Coolant Temperature Sensor |
| Engine Coolant Temperature Sensor 2 | Engine Coolant Temperature Sensor |
| Engine Oil Temperature Sensor | Engine Oil Temperature Sensor |
| Battery | ECM receives the battery voltage signal. |
| A/C auto amp. |
|
| Combination meter | ECM receives the vehicle speed signal via CAN communication. |
| ECM | ECM |
| Multi-way Control Valve | Multi-way Control Valve |
SYSTEM DESCRIPTION
The multi-way control valve changes the paths to heater, engine oil cooler and CVT oil warmer, and radiator according to engine coolant temperature and driving conditions. When coolant temperature is low, the paths to heater, engine oil cooler and CVT oil warmer, and radiator are closed and coolant is circulated only inside the engine to accelerate engine warm-up. When coolant temperature is high, the paths to heater, engine oil cooler and CVT oil warmer, and radiator are opened and coolant is refrigerated. This raises the coolant temperature and oil temperature rapidly and improves the fuel economy by reducing friction among parts.
Operation
When the ignition switch is OFF, the valve is fully closed to accelerate bleeding the coolant channels. When receiving a blower fan ON signal and/or an A/C ON signal, ECM opens the flow path to the heater even when coolant temperature is low.
| Valve position | |||
|---|---|---|---|
| Heater | Engine Oil cooler and CVT oil warmer | Radiator | |
| A | Full close | Full close | Full close |
| B | Open | Full close | Full close |
| C | Full open | Open | Full close |
| D | Full open | Full open | Open |
| E | Full open | Full open | Full open |
A: Closes all flow paths
,
, and
and circulates coolant only inside the engine. B: Opens the flow path to Heater and circulates coolant to Heater. C: Opens the flow path to engine oil cooler and CVT oil warmer and circulates coolant to Heater and engine oil cooler and CVT oil warmer. D: Opens the flow path to radiator and circulates coolant to Heater, engine oil cooler and CVT oil warmer, and radiator. E: Opens all the flow paths
,
, and
. The flow paths to the electric throttle control actuator and turbocharger are constantly ON. The high coolant temperature control is performed by opening/closing the flow path to the radiator to raise the engine oil temperature even when the coolant temperature is high. When engine load is high, the high coolant temperature control is not performed because of the knocking control. When detecting a malfunction in multi-way control valve, ECM fully opens the valve to secure cooling paths.