Just Installed BM-2 Battery Monitor and NOCO On Board Charger

Discussion in 'Gen 5 Prius Main Forum' started by VelvetFoot, Dec 9, 2025.

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  1. Gokhan

    Gokhan Senior Member

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    The BM2 battery monitor does not have a good way to estimate SOC, as it can’t measure and integrate the current, which gives the charge. The sensor in the car does that.

    Chances are that, since the car is always charging the battery when it’s cold, the BM2 battery monitor thinks the full charge is around 13.0 V, since the battery tends to be slightly overcharged because of constant charging.
     
    #41 Gokhan, Feb 2, 2026 at 4:21 PM
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  2. VelvetFoot

    VelvetFoot Active Member

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    I think it was an anomaly of some sort.
    I was in and out of the car figuring out where to put the tolls transponder. :)
     
    #42 VelvetFoot, Feb 2, 2026 at 5:29 PM
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  3. LRO

    LRO Junior Member

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    5th Gen EVAP Leak Check Conditions ... EVAP.jpeg
     
    #43 LRO, Feb 3, 2026 at 2:57 AM
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  4. VelvetFoot

    VelvetFoot Active Member

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    Good info.
    I always seem to get a followup dip two hours after the first five hour interval.
    It is cold in the garage though, below 40°F, but they do say 'typical', so there's that. :)
    Could it be something else? Sure. :)
     
    #44 VelvetFoot, Feb 3, 2026 at 7:07 AM
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