Blower motor issues

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by Jimbo22, Oct 21, 2025 at 1:56 PM.

  1. Jimbo22

    Jimbo22 New Member

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    I have hit a dead end. My AC had inconsistent flow for a few days then stopped blowing altogether. The heater does not blow either. I have replace all the fuses, the blower motor and the 12v battery with no success. When I turn on the fan it moves about 1/4 inch and that’s it. Any idea on where to go next?

    thanks
     
  2. PriusCamper

    PriusCamper Senior Member

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    Head to a junk yard and pull a fan... Of course maybe there's a fan relay that's failed? If it's a capacitor I would think that's probably built into fan, but have never taken one apart.

    Everything already vacumed out and cleaned?
     
  3. ChapmanF

    ChapmanF Senior Member

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    There's no relay (except in trims with the solar ventilation option, which have the SPDT relay that switches the fan power between the solar panel and the 12V system).

    The blower you put in, where did that come from? Does it test ok on the bench?
     
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  4. BiomedO1

    BiomedO1 Senior Member

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    Make sure your HVAC is clean and clear. Check your interior air filter and wiper cowl is clear.
    If your fan is not turning when activated, check connections and wire damage. Don't know if those has a ballast resistor, that sometimes opens up on other cars.
     
  5. ChapmanF

    ChapmanF Senior Member

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    No Prius generation had a blower resistor. Gen 1 and gen 2 had a blower motor PWM controller that mounted separately in the air duct, the same way older cars' resistors would be mounted, leading some people to still call it a 'resistor'. Gen 3 moved that into the blower motor itself and doesn't have the separate unit.
     
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  6. rjparker

    rjparker Tu Humilde Sirviente

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    First thing I would suspect is the replacement blower motor is bad. Unless it was new oem.

    I would check three fuses
    IMG_0361.jpeg
    Then do an active test with Techstream if available

    IMG_0367.jpeg

    Then check power and ground across the blower motor itself to ensure power and ground are good. A bad ground is just as bad as no power.

    Finally you need a scope or meter with graphing capabilities to check the SI pulse train input.

    Image.jpeg

    If the replacement blower is not new Toyota oem from Toyota then my bet is it's bad.