Coolant Pump
See Figure 1. The coolant pump (7) is located in front of the EVPT (5) and it circulates coolant through the system. The BCM controls coolant pump operation when the VSC (inside the ePTC) or OBC signals a coolant pump ON or OFF request. This only happens when certain conditions are met.
- BCM – Body Control Module
- ePTC – electric Powertrain Control Module
- EVPT – Electric Vehicle Powertrain
- MCM – Motor Control Module
- OBC – Onboard Charger
- VSC – Vehicle Supervisory Controller
Definitions
BCM Function
Start Coolant Pump – when following conditions are met:
- Pump requested - The VSC or OBC request cooling
- Vehicle upright - Tip over condition not detected
Stop Coolant Pump – when any of the following conditions are met:
- Both VSC and OBC request cooling off
- Vehicle tipped - Tip over condition is detected
- Critical pump fault detected
ePTC function
Start Coolant Pump – when following conditions are met:
- The propulsion system requests cooling when required
- The ePTC requests cooling through the VSC cooling signal
- Propulsion enabled - The pump shall not be enabled before propulsion is enabled
Stop Coolant Pump – when any of the following conditions are met:
- The ePTC coolant pump request may continue as long as required
OBC Function
Start Coolant Pump – when following conditions are met:
- The OBC requests cooling through the OBC cooling signal
- DC to DC Charging - High temperature in the DC to DC charging requires cooling
- AC Charging - When AC charging is occurring, the OBC may request cooling
Stop Coolant Pump – when any of the following conditions are met:
- The OBC coolant pump request may continue as long as required
Quick Reference Pump Operation
Table 1. Pump Operation
STATUS | Coolant Pump | |
|---|---|---|
On | Off | |
AC Charging | X | |
DC to DC Temperature high | X | |
Propulsion enabled | X | |
Vehicle upright | X | |
Vehicle tipped | X | |
Critical pump fault | X | |
Body Control Module (BCM) faulted | X | |
Onboard Charger (OBC) faulted | X | |
Open circuit to coolant pump | X | |
Pump will run after vehicle shutdown until 80 °C (176 °F) is reached or one minute, whichever occurs first. | ||
Coolant Flow
| 1. | See Figure 1. Radiator (3) to onboard charger (1). | |
| 2. | Onboard charger (1) to coolant pump (7). | |
| 3. | Coolant pump (7) to inlet fitting (6). a. Coolant flows through the vehicle sensor control (VSC) and motor control module (MCM) which are internal parts of the EVPT. | |
| 4. | Outlet fitting (4) to radiator (3). |
| 1 | Onboard charger |
| 2 | Filler neck |
| 3 | Radiator |
| 4 | Outlet fitting |
| 5 | Electric Vehicle Powertrain (EVPT) |
| 6 | Inlet fitting |
| 7 | Coolant pump |
Figure 1. Coolant Flow