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New Hybrid Battery Fan Not Working

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by Silver_Bullet_2012, Oct 15, 2022.

  1. Silver_Bullet_2012

    Silver_Bullet_2012 New Member

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    Previously had clogged hybrid battery fan (hybrid system failure message on dash) and I cleaned out the fan and was good to go.

    Yesterday I was cleaning car and forgot to put filter in hand held vac and it started blowing dust everywhere in car. Start the car and I get hybrid system failure light again. Took to autozone and it read code P0A80.

    Took the fan out cleaned it, but it still wouldn’t start. ( I am just plugging the fan in, not necessarily fully bolting it back in)

    so I went to Toyota dealership and got another fan for $220. This fan is not starting either. I checked the fuses and all look good. Once again I’m getting code P0A80. Old and new fan both won’t start spinning, and I just a click noise when it tries to engage for the first time when car is started.

    Any thoughts?
     
  2. Silver_Bullet_2012

    Silver_Bullet_2012 New Member

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    To follow this up I’m getting double click noise from back battery in rear of truck when starting car. Seems like maybe a relay back there. But I don’t see any relays (2012 model II)back there. Could it be the relays on the actually hybrid battery?
     
  3. ChapmanF

    ChapmanF Senior Member

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    It sounds like you might have at least two problems here, because a P0A80 code indicates a problem with the battery modules, not with the fan, and in addition to that problem, you are also reporting that the fan doesn't run.

    Do you have access to Techstream, or some other scan tool with active tests, such that you can command the battery fan to run, and thereby confirm or disconfirm any problem with that? I think some phone apps (Hybrid Assistant?) may also allow you to command the fan.

    At this point, I wouldn't be concerned about the click sounds. Yes, the battery does contain the system main relays, and they do click, so that part of the story doesn't sound like any problem for the time being.
     
  4. Silver_Bullet_2012

    Silver_Bullet_2012 New Member

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    Thanks for the reply Chapman! Yea I guess you are right about the hybrid relay clicks.

    Ordered OBD scanner should be here today!

    With my situation I’m 99% certain the hybrid battery is in very good shape. Seems like there is some relay/fuse preventing the hybrid battery from starting.

    I looked at all the fuses and tested the 12v battery.

    I also checked that the orange hybrid safety plug is securely latched.

    Does anyone know how likely it is that the fuse in the orange safety plug blew? Is there a way to visually inspect that fuse for damage?

    I will update with obd codes soon
     
  5. bisco

    bisco cookie crumbler

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    how's the 12v health?
     
  6. Silver_Bullet_2012

    Silver_Bullet_2012 New Member

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    I ended up disconnecting the white hybrid cable to the main fuse box under the hood (prob could have just disconnected neg battery terminal) to reset the codes.

    it reset the codes and everything is working perfectly . I’m thinking maybe I just needed to do this after replaced the hybrid battery fan.

    going to scan it with Torque app tonight, but I think maybe it just needed to be reset after new fan installation
     
    nicoj36 likes this.
  7. ChapmanF

    ChapmanF Senior Member

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    Replacing the fan doesn't require resetting anything. You are most likely experiencing the brief euphoria that everyone gets when they discover they can make the car's computers temporarily forget that they reported a problem.

    If you had a P0A80 code, the car noticed a performance spread between the battery modules wider than the limit for an acceptable battery. It will take a while for the code to come back, because you have just made the computer forget about it, and it doesn't make snap judgements to set P0A80, it will need to notice the problem again on multiple trips.

    The relays are there so that the car's power management control ECU is in control of when to bring the battery online. If it sees a reason not to, it won't. That's usually what's happening when the relays aren't closing.

    If it hadn't been, the code you'd have had would have been P0A0D.

    If it did, the code you'd have had would have been P0A95.
     
  8. Silver_Bullet_2012

    Silver_Bullet_2012 New Member

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    Thanks for this reply Chapman!

    I was thinking the same thing. I finally got a OBD dongle and torque pro app running. All 14 of my HV hybrid battery blocks are showing around 16 volts ( The lowest is 15.8 volt right after starting car). My aux battery is at 14 volt.

    Any ideas on what data I should look at? It is possible the broken fan threw the p0a80 code?, and reset cleared it after new fan install? I'm so confused.
     
  9. Silver_Bullet_2012

    Silver_Bullet_2012 New Member

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    I just found out powertrain sensor stuck. Could this be throwing the error ?
     

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