Hybrid Battery Fan mistake to headache

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by Justdsnce3, Apr 5, 2026 at 2:57 PM.

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  1. Justdsnce3

    Justdsnce3 Junior Member

    Joined:
    Nov 25, 2024
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    Location:
    Akron
    Vehicle:
    2008 Prius
    Model:
    Base
    Hey Yall, so to begin, I wanted to do some preventative maintenance on my gen 2 Prius which recently had hit 200k mi. So I decided to clean out the Hybrid Battery cooling fan. I didn’t have an air compressor to clean it out with and cleaned it out with water instead, I made sure to avoid the electrical connector as much as possible. I still dried with a fan with like 20-30 minutes.

    When I put it back in, it took about 20-25 miles to throw a P3000, C1034, and P0A84. So I checked the electrical connector to the fan and it was there right and snug. I thought simply the fan was bad so I bought another used fan (-40$), and same thing happened. 20-25 miles yada yada. So I started testing out parts, jumping them individually and so on. To my surprise the water cleaned fan jumped perfectly fine. Fast forward a bit, I’ve checked out parts and I replaced the blower motor controller because I thought it was the problem. It wasn’t. (-20$)

    So still in my diagnosing, i was checking the b14 battery fan relay. I was testing its resistance according to picture. 12v to relay pin 1 and 2, and probed 2k ohms and results were 0.01 ohm converting to 10 ohms of resistance. So I checked the 10A batt fan fuse. My test light showed it was okay, however when I multimetered it, dc volts, it displayed 6-7v. And the fuse socket displayed 3v.

    so I’m asking, whats the next step I should take? I have not done electrical diags before. I literally just bought a multimeter. Also my hybrid battery is working just fine, I’m getting 35-40 mpg usually still but I haven’t driven long distances in one sitting due to this issue. I’ve also added media that I’ve been using.
     

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  2. Tombukt2

    Tombukt2 Senior Member

    Joined:
    Nov 29, 2020
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    Location:
    Durham NC
    Vehicle:
    2009 Prius
    Model:
    Base
    Go in the back of the car rightabove 12 volt remove that panel enuff to pull it out . They're the infamous white plug that gets corroded .lotsa videos about it .