That must be frustrating as h@ll! Tell them about that wire connection on the thermostate, they may be game for anything at this point? Good luck, H

 

Definitely keep us posted Kristian!

Steve

 

I dropped the car off at the dealership last night and just got off the phone with my service consultant. He had two techs drive around and neither of them could reproduce the problem. They then called American Honda and found out that this is something that Honda knows there is a problem, and they are trying to diagnose what is going on.

Just like most of us here, they think that it is probably a temperature sensor somewhere that is causing the battery to go into panic mode. Seeing that I've experienced it in everything from 70 to 90 degree temps, I don't think that it is extreme heat causing the issue (like people are experiencing in 100+ temps).

The service consultant went through a 20 question questionaire from American Honda with me asking about my commute (hills, distance, temperature), my AC usage (no-windows, yes-on, or yes-auto), where the car is parked (garage, parking lot, sunny, shady, etc.), and the status of the 12v battery (which they are going to check for me).

If you are experiencing FREQUENT (like 2-3+ times monthly) battery recalibrations, I would highly recommend you bring your car in to your dealer. Give them the details about your situation and tell them to contact American Honda for more details on what to check/ask.

Like last time, I will keep updating this thread as I get more information.

 

Well, after making the comment that this had never happened to me, it happened on my way home from work. '06, 22,330 miles. 81 deg. F ambient temp. I had just climbed a long, steep hill. SOC was at 5 bars going into the hill (I think). When I stopped at the next red light, I was surprised to find it didn't go into autostop. So, I shut it down 'til the light turned green. When I started to accelerate, I noticed sluggish response, looked down and saw one bar on the SOC.

Does anyone know if that thermocouple wire is accessible, or is it buried in the battery pack?

 

I just took the car back in. Previously I was told the mechanic had reproduced the problem of the IMA battery crashing in warm (80 degree) weather. Today, they said they looked at the records and that no he didn't! IMA crashes in hot weather are normal they say.

Has anyone come up with a real fix (not turning on the AC in 110 degree weather is not an option and my workplace does not have any shady areas to park in). This is not just an MPG issue, but a safety issue. When the IMA doesn't provide the Assist, the acceleration is dangerously slow when merging onto the freeway.

I would be okay with the IMA dying if the car had enough acceleration without it. Is there any way to improve the acceleration of the car in general? Does changing to one of those K&M air filters work?

thanks,

- Frank

 

Ftlum, I have the Accord and I was looking at the manual the other day. There are air vents below the rear windshield and also in the trunk (right side) so that air gets to the IMA battery pack and Power Control Unit. It is important to keep that stuff within in a certain temp range or Assist and Chrg stops occuring. I live in AZ so I run my AC and I hope/assume it is keeping my battery pack happy. Many others are reporting this crash and erratic behavior. I wonder if in some of these instances, the temp sensors (they might be thermocouples or thermisters or ??) are giving the IMA brains bogus temp data so the car stops operating properly. My friends have an 06 HCH and I'm going to ask them if they are seeing weird things going on with the SoC and Assist/Chrg.

I guess having the V6 gives me a little extra safety cushion if the IMA decides not to kick in!

 

I have a 2007 HCH II. For the first 9000 miles (10 months) I had no SOC recalibrations. In the last month, I've had two.

Interestingly, they seem to coincide with a significant change in my driving habits. Up until about a month ago, I found best mpg driving at constant RPM, letting speed drift a little up and down as the CVT desired. That gave me 47.5 mpg average. Then I read somewhere a better strategy is to minimize "assist bars." That increased my mpg by 4-5 mpg to the low 50s, but I've started to get the recalibrations.

That caused me to look through past posts. I found this post that says more agressive driving (more SOC up and down bars) results in less recalibrations:

http://snipurl.com/3hdhx

I'd have to say that consistent with the experience I've had. I'm getting more recalibrations, after I changed to dramatically reducing the amount of assist I use.

For those of you with frequent recalibrations, what is your driving strategy?

 

I use as little assist as possible, but that's still quite a bit given my hilly commute. If I'm starting from a stop, I will let it assist as much as it wants to for my sub 2,000 RPM acceleration until I get to about 20mph and then I will start letting up on the gas to try to get the white bars to go away. On hills, I try to minimize the asst as much as possible, but I frequently find that it want to use 3-4 bars.

On a slightly related note (I think), my car has lost the ability to auto-stop on two occasions now in cold (~55 degree) damp weather. Yesterday I drove for 30 miles in suburban traffic and never got an autostop. This morning, it was actually colder (50 degrees) but it was auto-stopping just fine, however it wasn't raining. I really think there is some sort of temperature gauge on the IMA system somewhere that is out of wack.

 

I drive like Kristian - try to minimize assist. I get recals about once a week - always with the A/C running.

Something that has appeared in recent weeks is a forced regen of one or two bars even when my battery SOC is high (5 or more bars). Not sure what that's all about - happens even with A/C off.

My FE is still good though - currently showing 59.7 at 200 miles into this tank.

 

I finally found a post I can use. I was wondering if this is normal.

This happens to me every single day during the summer. I get into my car at about 5 PM and within 2 minutes I have zero battery. Every single day. I did read in past posts that temp above 100 are when the batteries aren't very happy. Well the car sits in these types of temps every day here in Phoenix. I took it into the dealer the first couple of times it happened and got the usual run around.

Now I am just careful on my evening commute.