I was thinking that my 12v batt was going out or something was causing a drain because for about a week now the main pack would not keep charged. Today on the way to work I was expecting an autostop but instead the car started charging. The pack went from about a third to nothing in a second flat, would not autostop and started charging. It seems to hold a charge better now after the "recal". Does all this sound right? How often you all have recals?

A recalibration means the computer sets a new full and empty mark as the battery loses capacity, so I guess it bases when to charge and how much to assist on that calibration since nothing else really changed about the battery.

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'97 Prius Simulation Prius inner workings

LakeDude, I think I have seen an event similar to your description twice in my 2G Prius.

Each time, the battery icon went from 5 - 6/8 bars down to 2 bars in a matter of seconds, and then the engine came on to charge the battery for a couple of minutes. MPG that trip suffered mightily each time.

The first time, I was running the AC from electric while stopped for a couple of minutes. After I started driving -- mayber a couple hundred yards, the battery drop occured.

The second time was more enigmatic to me. I drove a decline route that charged the battery almost full as usually occurs, and reached my destination. I was parked for about two hours, and on my way back home, the quick battery discharge happened again shortly after beginning the return trip. This particular route is home -> gym -> home, and is done often and no differently each time.

Functionally, it seems as though the Prius loses track of the true battery charge for a bit, and when the real state of affairs is noticed, goes into 'oh, ****' mode. But I cannot explain how my battery would have been discharged after the trip down elevation in the second episode.

I have not noticed any negative effects after each episode, although I get mighty nervous each time. There is always a lingering worry that my HV battery is not quite as young now, and some cumulative damage may be accruing -- but I do not have any real reason to think this is true.

I'm sure you read the thread here over at insightcentral regarding recals in an insight. I was impressed most by Honda's refusal to view a partially degraded battery as a valid reason for warranty replacement, even though it seemed to me, that the algorithm in use at the time that allowed more variance in battery SOC was facilitating battery degradation. Bad treatment of early adopters. I haven't heard of similar stories in the HCH, but I think the moral is pretty clear: don't push your HV to the limits on purpose.

R2-E2, 2G Prius.
Highway/City/Husband/Wife MPG: 56.5, as of 12/2005, 26K miles

Jac Nasser, Ford President: "We are planning to launch a hybrid version of
this car [P2000] within this year [1998]. We will also make FCEV available in
2004."