P0A93: Inverter A Cooling System Performance
What to do
This is the cheap warning — the cooling loop flagged before the electronics actually cook. Have the loop checked promptly: level, pump operation, air, and the small radiator's face. It is one of the best-value repairs in the hybrid range.
What this code means
The inverter's cooling system is not performing — the loop itself judged as a system, before the overheat it exists to prevent.
This is the code that precedes P0A3C: temperatures climbing faster than the loop should allow, or the loop failing a self-test, without the inverter yet crossing its limit. The corpus's coverage of this loop is now complete in one chain — the pump's circuit at P0A05–P0A07, its temperature sensing at P0A00–P0A04, this performance verdict, and the overheat consequence at P0A3C — and the diagnosis is the same five-minute list every link shares: pump running, level correct, no air, radiator clear.
Catch it here and it is a pump or a bleed; ignore it and it becomes derates, then P0A78's expensive conversation.
Likely causes
Start here
- Faulty inverter coolant pump · moderate
- Low inverter coolant level · easy
- Air trapped in the inverter cooling circuit · easy
Less common
- Restricted low-temperature radiator · moderate
Symptoms
Components involved
Information, not instruction
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Have anything you intend to act on checked by a trained person against the manufacturer's own procedure for your vehicle. Nothing here replaces that procedure.
Community experience
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