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Hybrid Vehicles/Prius Unexplained Battery Drain...


Hi there and I hope this e-mail finds you well. I own a 2007 Toyota Prius which has been running quite well until recently. Recently, I've experienced unexplained instances where I attempt to start the car to find that it won't start and has no power. I have it jumped and it seems to come back okay...until the next time. I've noticed that the Prius runs fine and holds a power charge after a long drive (30 minutes or more). However, if I take it on a short drive, the car comes up drains a few hours later. I've heard a few opinions on what could be happening, but what do you think. Also, in the interest of full disclosure, this car still has the original batteries in it. Thanks and I hope to hear from you soon.

I can only take a wild guess that some connector has gotten a bit corroded, and your control circuits are getting a bad signal.  If the battery passes the usual tests for serviceability, that's a lot of energy going missing.  Presumably, something is heating up, which should be fairly easy to find.  Or, maybe it is just time for a new battery.  I don't have any special information on your model - sorry.

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Bob Stuart


I'm best on questions of the suitability of new technologies, but will try to keep up with retail offerings of hybrid vehicles too.


Designing human-electric hybrids.

International Human Powered Vehicle Association

4th Annual Velomobile Seminar proceedings, many listserv postings.

few academics, but my 1st prototype won a world championship, and I've lectured to engineers.

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