Hi,
I've noticed that, at times, my 'assist battery' is very low...just one little bar. It eventually recovers but two questions: 1) Is that normal/OK? 2) Is there something I'm doing, in my driving, to create that condition?

Hi Brian:

___That does not sound normal at all. Are you constantly using quite a bit of IMA on every acceleration and not really receiving any regen during any stop? Why not consider the “headlights on” trick to see if that helps. The next time you are heading off for a 20 + minute drive, turn your headlights on as that is one way to force charge the Ni-MH battery (hidden forced charge) and see where she ends up after the 20 + minute outing.

___Good Luck

___Wayne R. Gerdes
___Waynegerdes@earthlink.net

The first 2 months or so after I first bought my car the IMA always maintained 90% SOC.
After the 2 months it varied between 1/3-2/3 and rarely made it back up to 90%.

I'd use a small amount of Assist, drive 5-10 miles, use a little more, 5-10 more miles and eventually it would work down to 1/3 (Or less).

4 Bars of charge would turn off/on seemingly at random and hidden charge was intermittant at best......But only during my day commute. It always maintained 90% at night due to headlighs switched on.

I had my dealer look at it and after the 5th time saying it all is OK, I just resorted to always driving with lights on.

A few months ago I thought:
...Hmm.... I wonder if the IMA truly is managing it properly, and I've been bypassing proper maintenance with my lighs always on?

Anyway I've recently shut them off during the day and sure enough it is functioning like it used to. But I figure that's OK as it doesn't seem to hurt my MPG at all. Since the 2nd half of my travel is at night, it gets a good full 90% charge at that time.

I agree with xcel that one bar is not normal unless constant use of Assist.
If that isn't the case I think you likely have a problem somewhere.
What is your tank MPG? That may be a tell-tale.
Ether way I'd try the headlight trick.

Efficient drivers do it better.
1003 miles a tank personal record. 74MPG calculated. HCH1 CVT

Even when the battery appears completely empty to you, it still has 20% charge so it won't hurt the battery too much being that low, and when it appear to be full it's at 80% charge. This is done to give the battery a longer life since they generally have a limited number of full cycles before the capacity and internal resistance degrades.

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