Solar Charging Roof Not Working!

Discussion in 'Gen 5 Prius Main Forum' started by maiki, Oct 30, 2025.

  1. KMO

    KMO Senior Member

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    Good spot. The exact wording in mine is "In the following cases, charging the hybrid battery (traction battery) via the solar charging system is not performed. [...] The hybrid battery (traction battery) is completely discharged", which could mean just zero EV or significantly lower.

    Sounds to me like this could be the root cause, given the report that no miles have been added at all for months.

    @maiki - have you been at zero range for all those months?

    Scanning the thread, just noticed this post from @ATalkingRock , also complaining of no range increase, who then came back with

    Possibly the same thing - not charging because empty battery?

    Not charging when empty is extremely counter-intuitive - I can see this being the cause of a lot of user confusion. But it makes sense for two reasons:
    • Not having to cope with either low or high extremes of the battery simplifies the work of the solar charging system, so it's a reasonable design shortcut for an auxiliary charge function.
    • It's a fail safe in case the solar system ends up not generating enough power and ends up being a net drain. There must be a battery threshold below which the solar system won't activate the HV system to ensure it can't accidentally let the charge drift too low.
     
    #121 KMO, Jan 16, 2026 at 1:31 AM
    Last edited: Jan 16, 2026 at 1:54 AM
  2. Gokhan

    Gokhan Senior Member

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    When he posts his Wh screen for solar, this discussion will end. If he did that in his original post, we would never have had this discussion.