We have an Arduino connected to the comm’s connector (TX/RX and GND).
The Arduino (with some code) is reading lot’s of data. One of it is the temperature.
When the temperature is above a set value, the Arduino will trigger a small relay what will turn on the pump.
The Arduino is in our case also used for pre charging. IE. Turning on the main relay when a set value has been reached to power the VESC, and a small relay to turn on the receiver.
Running the VESC without a pump is possible. We did it, but it will as mentioned above thermal throttle, and for us it was always at the wrong moment
The “problem” with the forced induction (water being forced into the VESC by forwards movement) is that it will only cool when you are moving! As soon as you stop, the cooling will also stop.