[VW TECHNICIAN]

The picture doesn't show that, though, does it? It shows hot fluid entering this heat exchanger and cool fluid leaving it. (It also ignores the fact that the PTC Heater heats the fluid, but showing heating/cooling on the same diagram was probably viewed as too confusing).

BTW, my Volt has the exact same heat exchanger that @VW TECHNICIAN is describing and it's for exactly the same purpose: cooling the battery (and the drive electronics? I can't recall.) cooling loop in the summertime when its hard to reject heat to the ambient air via the radiator.

Quite similar across the board....but ID has integration of bypass valve for refrigerant when air-conditioning is called but dosent need to cool down HV battery.