IMA limited when Hot or Cold
 

Since I found this group a great place to get inforamtion the dealer would never tell you, I thought I would mention a useful bit of information on the IMA. This information is target at those folks that have a short commute or use their hybrid mainly for short (10-15 min.) periods of time.

If the IMA battery is too hot or too cold, the IMA limits the battery output to protect the battery. This disables IMA assist and Auto-Stop (Auto stop is depended on a number of factors and there are other threads that discuss those in detail). What this means is the IMA will not function for the first 5-10 minutes when cold (i.e in the dead of winter that many areas are in now) or for 15 or so minutes when the battery is HOT (Summer time).

Again, if your trips are mainly short, it is good to keep in mind the IMA will offer little help in extreme temperatures.

Re: IMA limited when Hot or Cold
 

Larry,
I have mainly a 15 min commute to work. Would a block heater help the IMA to work sooner? Does Honda make one or will any aftermarket/auto parts store item do the trick? I'm sure an insulated garage would help also.
Thanks, :lightbulb
Don

Re: IMA limited when Hot or Cold
 

Don, Based on what I have observed, I would say a block heater would help. This would allow the coolant to already be warm and thus reduce the time it take for Auto Stop to kick in.


Here is a link to an online store that sell Block heaters for 2006 HCH. Note there is a link on installing this part, which should let you know if it something you want to try or if you want to have someone do it for you

http://www.anythinghondaonline.com/i...OD&ProdID=1086

Our temps have not been extremly cold since I have owned my HCH, so the time is takes for IMA to kick in has been fairly short. A block heater will not warm the battery, which seems to be what Honda says is being protected by limited the IMA.

Re: IMA limited when Hot or Cold
 

Larry,

Are you sure about this? I agree that you don't get any regen for a few minutes when it's cold, but I get plenty of assist right from the start - down to -5F, at least.

Re: IMA limited when Hot or Cold
 

subnivean - My input was based on what was in the Owner manual and what I have seen / heard otehrs report. As noted, the tempertatures have not been extremly cold where I live, so have not noticed the lack of assist myself, however as you noted, have seen lack of regen and of course the lack of auto-stop, until the coolant is warmed up.

Again, I HAVE heard other owners question if the lack of assist when cold was by design, which is why I originated the post.

Re: IMA limited when Hot or Cold
 

When cold, in the morning, the REGEN WON'T kick in, but I DO get some assist, most of the time. Actually, I've noticed that its the temp of the BATTERY, and not the external temperature, and not the coolant temperature. I assume this because the regen has kicked in at various levels of coolant temperature, and at different times with different external temp. I haven't had the chance to test it when hot....

Re: IMA limited when Hot or Cold
 

I *do* remember now that the manual seemed kind of fuzzy on that point; I'll have to check later.

On the bright side, yesterday is considered the coldest day of the year around here (average of 8 low, 26 high). It varies by region, but I think everyone's on the way up now! :shade:

Re: IMA limited when Hot or Cold
 

Is this the same way the HCH1s worked? Can the previous generation owners shed some light on this?