Engine Cooling - Vehicles With: PHEV (G2856524): Operation: Notes
Engine Coolant Circuit Flow Diagram
A = LOW TEMPERATURE COOLANT: B = HIGH TEMPERATURE COOLANT: C = COOLANT BLEED ROUTE.
| ITEM | DESCRIPTION |
|---|---|
| A | Cylinder head |
| B | Cylinder block |
| 1 | Heater core |
| 2 | Coolant expansion tank |
| 3 | Charge air cooler |
| 4 | Charge air cooler coolant pump |
| 5 | Coolant degas separator - Charge air cooler circuit |
| 6 | Charge air radiator |
| 7 | ATF cooler |
| 8 | Auxiliary coolant pump - ATF cooler |
| 9 | Auxiliary radiator |
| 10 | Radiator |
| 11 | Auxiliary coolant pump - HV interior heater |
| 12 | Changeover valve |
| 13 | Auxiliary coolant pump - Heater core |
| 14 | HV interior heater |
| 15 | Electric throttle |
| 16 | Engine oil cooler |
| 17 | Variable coolant pump |
| 18 | Turbocharger |
| 19 | Engine coolant degas separator |
| 20 | Electric thermostat |
When the engine is running, the engine coolant is circulated around the engine cooling system by the variable coolant pump.
At engine start-up the variable coolant pump shroud is in a closed position, blocking the engine coolant flow in the cylinder block. When required, the HVAC Control Module (HVAC) can request the opening of the variable coolant pump shroud to provide the required engine coolant flow. The HVAC communicates through High Speed (HS) Controller Area Network (CAN) comfort systems bus with the BCM /GWM .
When the engine coolant is cold, the electric thermostat is closed and the engine coolant flows directly back to the variable coolant pump.
When the engine coolant reaches operating temperature the electric thermostat begins to open. This allows engine coolant flow through the radiator system to provide the required engine cooling.
When the electric thermostat is fully open, the majority of the engine coolant is passed through the radiator to the variable coolant pump. With a proportion still passing through the turbocharger, heater core, electric throttle and oil cooler.
Expansion and contraction of the engine coolant is accommodated by an air space in the coolant expansion tank and the compliance of the flexible hoses.