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Radiator fans do not operate at low speed, only high and overheating

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by robert90, Jul 13, 2024 at 9:37 AM.

  1. robert90

    robert90 New Member

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    A ventilátorok nem működnek alacsony fordulatszámon. Amikor bekapcsolom a légkondicionálót, mindkét ventilátor nagy sebességgel működik. A biztosítékok rendben vannak. Ha a hűtőfolyadék eléri a 95 °C-ot, a ventilátorok nagy sebességgel kapcsolnak be. Techstream-el tesztelve a ventilátorok jól bekapcsolnak. A két ventilátort még nem láttam alacsony sebességgel futni. Hozzáteszem, hogy jelenleg 37°C van kint árnyékban és a kompresszor is elég hangosan dolgozik. A két ventilátornak valamikor alacsony fordulatszámon kell működnie? Tegnap az történt, hogy túlmelegedett a hűtőfolyadék (117°C) és megjelent egy piros háromszög, és le kellett húznom. Amíg várakoztam és készen állt az autó, nem hallottam a ventilátorok működését. Lehetséges, hogy az autó letilt minden működést, amikor megjelenik a piros háromszög?
     
    #1 robert90, Jul 13, 2024 at 9:37 AM
  2. bisco

    bisco cookie crumbler

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    translator didn't work
     
    #2 bisco, Jul 13, 2024 at 1:45 PM
  3. ChapmanF

    ChapmanF Senior Member

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    Google Translate says "Hungarian - Detected" and offers the following:


    The fans do not operate at low speed. When I turn on the air conditioner, both fans run at high speed. The fuses are fine. When the coolant reaches 95°C, the fans kick in at high speed. Tested with Techstream, the fans turn on well. I have not seen the two fans running at low speed yet. I would like to add that it is currently 37°C outside in the shade and the compressor is also working quite loudly. Do the two fans need to run at low speed at some point? What happened yesterday was that the coolant overheated (117°C) and a red triangle appeared and I had to pull it off. While I was waiting and the car was ready, I didn't hear the fans running. Is it possible that the car disables all operation when the red triangle appears?
    ​
     
    #3 ChapmanF, Jul 13, 2024 at 2:08 PM
  4. ChapmanF

    ChapmanF Senior Member

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    Low speed is obtained by controlling the fan relays so that the two fan motors are electrically in series. High speed connects each fan across the full 12 volts, effectively in parallel.

    The fact that both fans work, and can be seen running at high speed, should allow focusing on what might be at issue for low speed. The diagram looks like this:

    [​IMG]

    Someone highlighted the low- and high-speed power paths, in this image:

    [​IMG]
     
    #4 ChapmanF, Jul 13, 2024 at 2:14 PM
  5. Fred_H

    Fred_H Misoversimplifier

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    Edit: Sorry, the earlier comments didn't show up when I posted.

    Google translation:

    The fans do not operate at low speed. When I turn on the air conditioner, both fans run at high speed. The fuses are fine. When the coolant reaches 95°C, the fans kick in at high speed. Tested with Techstream, the fans turn on well. I have not seen the two fans running at low speed yet. I would like to add that it is currently 37°C outside in the shade and the compressor is also working quite loudly. Do the two fans need to run at low speed at some point? What happened yesterday was that the coolant overheated (117°C) and a red triangle appeared and I had to pull it off. While I was waiting and the car was ready, I didn't hear the fans running. Is it possible that the car disables all operation when the red triangle appears?
     
    #5 Fred_H, Jul 13, 2024 at 2:17 PM
    Last edited: Jul 13, 2024 at 2:23 PM
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