Kühlmittelpumpe des Wechselrichters defekt

The electric pump circulating coolant through the power electronics' own low-temperature loop — a separate system from the engine's cooling, with its own reservoir and often its own small radiator, because inverters must be kept far cooler than an engine runs.

When it stops, the inverter overheats while the engine's temperature gauge reads perfectly normal — the misdirection this part is built around. An electric pump also fails silently: no belt to squeal, no visible leak required, just an inverter that derates or cuts drive on warm days and recovers after cooling. Checking that the pump actually runs, and that the loop's reservoir is full and free of air, is a five-minute job that resolves a disproportionate share of inverter over-temperature and performance codes.