2010 prius inverter coolant temp affecting ac opperation?

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by trozei123, Jul 27, 2026 at 7:38 PM.

  1. trozei123

    trozei123 Junior Member

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    This whole summer, my wife's 2010 prius has been having intermittent periods where the ac will just stop working and blow hot air. i have tried diagnosing the issue using the Hybrid Assistant app that monitors the temps of the engine, electric motor, inverter, and hybrid battery. during the day, i have seen the inverter temp get as high as 158f, so i suspect that this is the problem. i have topped off the coolant in the inverter reservoir and also checked to see if the pump could be bad. i do see a slow rippling of coolant inside, and i am wondering if it should be more turbulent to indicate the pump is working. no engine light and no codes pertaining to an overheat condition.

    i have had the ac compressor replaced last year, and the ac does work when the temp outside is cooler, but this is my wife's dedicated work car since she does delivery work for doordash and grubhub. any ideas on how i can address this issue?
     
  2. BiomedO1

    BiomedO1 Senior Member

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    Sorry; that's not a diagnosis - but a guess. You need to take it to a shop or have a friend that KNOWS what they are doing help you. One quick test is to turn on the AC - full blast and check the engine cooling fans are turning. Dead cooling fans won't allow the heat exchange to take place.

    Good Luck...
     
  3. trozei123

    trozei123 Junior Member

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    Both cooling fans are running full blast with the ac turned on full blast. The only issue is that it will quit working when the temperature is too hot outside.
     
  4. BiomedO1

    BiomedO1 Senior Member

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    Sorry; that's about the only easy, tool-less check you can do. You can take it back to the guy that did the compressor; because he obviously didn't fix it right. Unless they can find a pin hole in your condenser from road debris. IMHO: If the AC job was done correctly, it should last more than a year - unless road debris punched a hole in the condenser. The system could also be over pressurized - too much Freon or too little; because that's a variable speed compressor and should be filled by weight - NOT pressure. Shade tree mechanics makes those kinds of mistakes all the time; but your system will work when you drive off - the "fix" just won't last....:(:censored::cry::whistle:

    Sorry.....