Inverter water pump going bad?

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by Shaun H, Jun 29, 2026 at 2:20 PM.

  1. Shaun H

    Shaun H New Member

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    Four
    I noticed my MG1 and MG2 get to about 200 degrees Fahrenheit after delivering food for two hours in 100-110 degree Arizona weather. It seems like the acceleration is not as good as when it’s cooler. Wondering if maybe the water pump is going out and not able to keep up?

    I’m using hybrid app to monitor temps.
     
    #1 Shaun H, Jun 29, 2026 at 2:20 PM
  2. Higgins909

    Higgins909 Member

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    III
    I think it's normal. IIRC, I hit almost 300 when I tow my boat. Something like 240 when I would Uber. BTA would hit 200 all the time. I confused it with BTA or maybe I'm confusing them now. One is the HVB and the other is a part of MG1 or something like that. Scangauge 2.
     
    #2 Higgins909, Jun 29, 2026 at 7:29 PM
  3. PriusCamper

    PriusCamper Senior Member

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    You'll get warning lights and error codes if anything goes wrong... What you're probably experiencing is the computers are balancing the gas engine with the electric motor differently than they would if the weather was less extreme. Another symptom you might notice is the computers send less power to the AC system and it won't work as well at full blast.
     
    #3 PriusCamper, Jun 29, 2026 at 7:32 PM
  4. PTS

    PTS Member

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    MG2 alarm limit is 374f
    MG1 alarm limit is 232f

    Inverter coolant temp is more likely to code with a 149f limit
     
    #4 PTS, Jun 29, 2026 at 8:20 PM
    Brian1954 likes this.
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