Under normal circumstances my IMA battery stops assisting the motor when it gets down to about to 25% capacity (two bars). When this happens it is very noticeable in that the engine has to work considerably harder. You know when its happening. Well yesterday on my way home from work it stopped assisting but this time I had about 75% left (six bars). I felt the engine working harder and the assist would not go above one bar. I floored the gas to try and make the assist kick in but it would not go above two bars which is nothing. It lasted for about 5 minutes and then stopped, everything seemed normal. About 10 minutes later it happened again, lasting about 5 more minutes. Has anyone else experienced and is it something I should be concerned with?

 

The only time this happened was in 110 degree temperatures. I think the computers basically disconnected the battery... no charge or discharge... to protect the battery from excessive temperatures. Can't recall a situation of this happening at any other time. I do, however, experience the same thing on the charge side quite often... meaning that it won't regen, even though conditions are just fine for regen. A few minutes later, all is normal again.

 

High temp will kill the 185v, I think it's trying to protect your batt.

 

dburanich...explain in more detail the temperature...were u using heat/air???

This happened to me yesterday. I was autostopped at a light(with the heat on)...but there was a lot of stop and go traffic. All of a sudden my bars started dropping and the engine turned on even though i had my foot on the break. I then had 0 bars and the battery was charging(3 green bars). I noticed it was really hard to accelerate. It took about 2-3 mins to charge up to about 4-5 bars and then it worked fine after i kept driving. Had my car for 5 months now and this is the first time it has happened.

anyone else?

 

Outside temperature was 85 degrees. No heat and no A/C. It was a beautiful day out so I was driving with all the windows down.

 

Vince, I've experienced what you did 3 or 4 times now in 4000+ miles. The most recent was yesterday! Shocked me too, as it had not occurred in quite a while. I started home from work with only 2 bars (I think listening to the radio at lunch used up more of the battery than usual). Anyway, within a minute I was down to 1 bar, then after another minute or two, zero bars. At this point I had to stop for about my 4th time early on in my trip home, and the car didn't auto-stop. It didn't auto-stop when I had 1 bar either. When I got back going again, the assist would not help the little engine, making acceleration very weak. And the 3 bars of charging were on, to pump up the IMA battery quickly. After a few miles of driving/coasting I had the battery back up to 5 bars, and all was normal. By 10-15 miles into the trip, I was back at my normal 6-7 bars.

This is all NORMAL, I believe. The key is to not use up ALL the IMA battery charge, because the circuitry WILL force a charge on you and will not help the gas engine until it is sufficiently charged (3 bars is the minimum before it'll assist, I think).
You want to drive in such a manner so that the IMA battery is not really being used that much, except for in auto-stop situations. Mine stays at 5-8 bars most-times, and most often it's at 6 or 7.
Hang in there! I had some concerns about this too, early on. The car suggests strongly how it wants to be driven.
I accelerate quite slowy from a dead stop until I hit 10 MPH or so, then accelerate more aggressively until I get to speed. That way, I get to speed quicker, and can get in the 50+MPG range (most-times) quicker.
Keep your distance to reduce speed fluctuations (keep it reasonable, though).
When you know you've got to stop, make sure to brake enough to get the full regenerative charge for the longest time possible. Usually this means braking a little harder (not much, though) and a little sooner than you may be used to. I do this whenever my state of charge is not at least 7 bars.

There are lots of tips and techniques on this site to help you. They helped me - and I probably use less than 1/2 of them!

 

Thanks for the reply steve. I think ive been anticipating lights a lot and just taking my foot off the gas and that slows the car down enough..but like u said it doenst give the battery a good enough re-charge. Since this incident, I have been braking so that i get full charge for longer periods of time when i need it. Thats a good thing to keep in mind. Actually this morning my battery meter was at 8 and that hasnt happen since i got it from the dealer...4500 miles ago. Also, its amazing how much power the battery gives the engine. Its a huge difference when it doesnt use battery for the initial push from a stop.

Another question. If im using heat(lets say i put it at 85) should i hit the A/C button so that it now displays "AC off" ?? Does that matter ?

 

I think temp. setting does not matter at all. If the display does NOT say A/C Off, it might be on. I haven't had the need for heat yet, but I think that's what others have concluded (in another thread or two - some time ago) on this site.