IMA Battery Crash?
 

Once each day now in two days of commuting I've looked down at a stoplight and seen my SoC with only 2 bars. Neither my driving style or my route has changed, and I was not using the IMA excessively. Both times I've experienced this, the car went through a forced regen cycle and then behaved normally with the battery coming back up to 6-7 bars which is where it usually stays for me.

Is this something I should be worried about? Has anyone else experienced something similar? The only thing different about the car was that I had the first oil change done last weekend, although I don't know how that could effect it.

Re: IMA Battery Crash?
 

It is becoming pretty common for some of us with the higher summer temperatures... Especially when operating the AC on Auto.

How warm has it been at your location?

MSantos

Re: IMA Battery Crash?
 

Both times were on the commute in so temps around 60 or so, and my A/C was not on (displayed as A/C Off so no phantom A/C).

Re: IMA Battery Crash?
 

I wonder if you experienced a battery recalibration either of those times. When these happen, you can watch your indicated SoC quickly drop down to no bars (1 bar at a time). Forced charging then occurs. Maybe you noticed it when the charge was already on the way back up. I've had this happen to me twice. Anyway, just a thought.

Re: IMA Battery Crash?
 

It happens to me frequently right now but I have temps from 110 - 120 which is not what you are facing so I am not sure. In our winters, tempe around 60-70, I did not have that happen ever. I also drive a flat route, may that be part of it?

Re: IMA Battery Crash?
 

I don't know, but it's possible. I've been watching the SoC like a hawk since it happened yesterday morning and haven't seen it since (although I drove the Sub today). Hopefully that is what was causing it, and it's done recalibrating now!

Re: IMA Battery Crash?
 

I had a similar battery crash experience about 1 week ago in my 2007 HCH-II. On that particular day the air temps were over 105 degrees and the AC was running on auto full blast. I got stuck in stop and go traffic on my commute home when it happened. My battery charge indicator plummeted until no bars were visible. I call that a crash.

Once I got moving again (following the traffic tie up) the car felt very underpowered because the IMA was no longer assisting the ICE. Seventyish horsepower ICE is not enough to propel a 2,900ish pound car. But I digress.

My car started to do "forced regeneration" even when at a stop. When at a dead stop the ICE automatically reved up to about 1,500 RPM, and then the green regen bars appeared on the charge indicator. This mechanical process was not pefectly smooth, but it did restore about 1 bar of battery charge within a few minutes.

Since that day, my car has returned to normal operation. But I found the experience somewhat "unerving", and it played on my fears about the reliability of the IMA Hybrid system.

Here is what I learned from research these symptoms online and in the owners manual. Page 69 of the 2007 Civic Hybrid owners manual describe the process of automatically recalibrating the battery guage on a periodic basis. That description is very similar to what I experienced (as described above). The manual states that "This correction of the battery level is normal and does not indicate a problem. If the IMA battery develops a problem or becomes deteriorated, the IMA system indicator will come on. If this happens, have the vehicle checked by your dealer as soon as possible." OK, I guess that means this "battery recalibration" is a normal operating process, and I should not worry about it given that the IMA light in the gauge cluster did not illuminate. Hopefully as the air temps drop back to normal (highs in low 90s), the process will not be repeated.

Has anyone else had this experience, and did it occur more than once? Please share your experience on this forum. Thank you:D

Re: IMA Battery Crash?
 

I've had it happen a couple of times in 16000 miles/1 year of commuting. The first time was heavy-stop-n-go traffic (mostly stopped :( ). Same experience as you had. BTW, the ICE is 90 Hp, plus 20 from the IMA system, for a total of 110 Hp. You're right, though, ICE alone is definitely sluggish.
The other couple of times this recalibration occurred (if that's what this indeed is) seemed to be random. At least to me.

Re: IMA Battery Crash?
 

I noticed this sort of thing recently as well. Recently, I had parked and went into a store. I'm fairly sure I had a few IMA bars left (I've never seen it run to zero while driving), but when I got back into the car and started to drive off, I noticed no IMA bars left. Unfortunately, I've not been able to figure out what I've been doing to trigger this. Weather here has been 90s-105 so maybe that's a factor. The car did not seem to rev up, so I don't think this was the recalibration that was described.


- Frank

Re: IMA Battery Crash?
 

So, does anyone feel that it is harmful to the battery if you leave it with a very low charge (like 1 or 2 bars) overnight. I know the battery is never really at 0, but does it hurt the charging power by leaving it low for 10-12hrs ??

I would drive an extra 5miles or 5minutes to bring up the charge.

just my thought.