I own a used 2006 HCH II, 88,100 miles. The 12v ran low so that the car wouldn't start soon after I got it (in late May), but it worked fine after being jumped, then was replaced a few weeks ago. Although I believe it was the original and it was probably time to get a new one even if it seemed fine (the dealership noted some problem with cold crank amps not being what it should), the motivation to get a new one was IMA forced recals.

Being new to the Civic Hybrid, I didn't think twice about having the software updated (in July, I think?). As others have commented, before the update the IMA was fine, after, well, it isn't. The IMA has a forced recal with every start-up. Sometimes it happens twice in 20 or so minutes of driving, but it always happens at least once. I can't remember how often it happened before the update, because it almost never happened.

What will happen is the SOC goes from wherever it is (5–full) down to 2. I can usually predict when this will happen because the green bars stop showing up when I brake, which I notice by no auto-stop, and sometimes the engine will kick in and the assist bars don't appear, even if the SOC looks fine. Then, it quickly falls.

After a bit of driving with the forced regen bars, the SOC might climb to 3–4 as if it's really being charged, but after that it always jumps up, bar by bar within five seconds, to full, and now I'll have complete IMA power. So, it seems like the battery was never truly depleted.

I did the 'reset' procedure before getting a new 12 volt: unplug the 12v for at least ten minutes, then drive to full, park, and check back*in the morning — the SOC would be where I left it, but with driving it would fall and jump back up as I've described. And before the new 12v was hooked up there was no 12v in the car for about an hour. I'm not sure if that would affect anything negatively?

With the new 12v, at first I noticed immediate improvement where I would get 45–49MPG (I was getting 25–30 before); now it's fallen down to 36MPG, and it's getting hard to maintain. (I need to put more pressure in the tires, but as far as I know that still doesn't help the recal problem.)

I test drove the car a bit with the new 12v — say 20+ miles at a time, highway and city, though I usually drive city. So I get to either drive in the city and my MPG implodes because of how long the assist is gone compared to how little distance I drive, or I go on the highway and run the engine into MPG-sucking RPMs just to get to speed, MPG which I can't build back up after the assist returns even during a long drive. It's been cold-to-nice here, so no air conditioning unless I use it with the AC off. The fact that it was a hot summer just a month ago didn't make any difference on recal frequency.

To test whether the forced recal was happening because of a certain time up running or because of a certain time/distance driving, I let the car idle for about five minutes a couple days ago (I know, it's not really good to do this), but the forced recal didn't come. After a few minutes of driving, with perfect IMA assist right after this idling session, it drops.

Is there any special procedure to follow to let the car recognize a new 12v, or anything that can be done so the car won't treat the IMA battery like it's empty when it seems it isn't? Or is this really a deeper problem, such as malfunctioning IMA battery? What would someone with more experience suggest? (Besides a visit to the dealership, which I'm about to do anyway.)

I've been reading up on here and on other forums, but I haven't found any answers that address a situation quite like mine, with recals after every start-up that jumps back to a full SOC after a few minutes. Though the new software update puts less load on the battery, I don't understand why it would cause many times more recals than before the update.

I've heard that Honda won't/can't remove software updates. Is that right? (I have a 950 mile trip to Mississippi at the end of November, and I was depending on the hybrid to get me great mileage... Before Honda's battery "life-saving" update, it would have.)

 

It's my understanding that the only way to roll-back the software is to replace the computer, an expensive proposition, I think. I would just hang in there, take whatever updates are offered, report all problems promptly to the dealership. The warranty is 8 years everywhere, isn't it?

We got the update about 2 months back, and are experiencing fairly frequent recals, stubbornly low state of charge, occasional miraculous jumps to full state-of-charge after a recal (can you hear the cynicism?). I figure give it a try, they can't fault you for "neglecting" updates, and it just might work in the long term. If the battery isn't already too far gone from the previous software itteration...

 

Arteggio... your problem has nothing to do with the 12v battery being changed. I have an 06 HCH and about two years ago it started operating strangely while at steady speed on the freeway. Took it to the dealer, they replaced the 12v battery and all was good.

Then earlier this year I started experiencing frequent recals, drops in the SOC, no IMA assist at times and MPG dropped. The first thing the dealer did was update the software and that made the performance unacceptable. It was like you are experiencing.

Long story short, Honda America agreed to replace the IMA battery gratis ($3,000+) the car was back to "normal". The battery did not test "bad" and there were no error codes. The last software upgrade does change the drive characteristics but after 3,700+ miles I am averaging 44MPG again.

I suspect that the latest software upgrade changes the operation of the IMA system and if your battery is marginal, you will know it in a hurry. The software upgrade may "help" the IMA battery to last longer but you are screwed if the battery is already marginal when the software is applied.

 

So my IMA Battery is on its way out? I have very same symptoms on my 07 HCH (108,650) with new software applied 3 weeks after (95,000) it was released. My IMA Battery goes from a full charge to 2 bars about 5 mins after startup. It doesn't matter what the temperature is outside battery still drops to 2 bars. The dealer told me the battery will always drop to 2 bars due to IMA system adjusting charge due to temperature.

 

That's a lie. I never had ANY recals EVER in 4.5 years of ownership of my 06 HCH. Now they are constant, day and night, cold and hot...all the time. It's a big lie...just like their lie to me... "sir, that is normal operation of your vehicle." I have purchased my last Honda.

 

I have never had a sudden drop on the SOC with my 2006. HCH2. H

 

What he describes is exactly, to the dot, what happened to my car. I replaced the 12v battery more than a year ago, so that is out of the question. But after having the latest upgrade applied to the car 5 days ago, every time I start it up it goes on the same recal cycle as described.

I posted a video in youtube:

http://www.youtube.com/watch?v=yH5KYT3t0Lk

If you got your battery replaced by Honda, they have my car now and I hope I get a new one too. My mileage had gone down to middle 30's.

 

I've been meaning to report back with this news, so, I'm finally here.

Foremost: a bit of loose success.

At the end of November I took a road trip to and from Mississippi from West Virginia (almost exactly 1000 miles one-way). After 300-500 miles on the highway, the battery finally stopped recalibrating at all — before this moment it had been recalibrating every twenty minutes, or less if I had to use it for an incline. (This moment also happened approximately 700 miles after replacing the 12v, but maybe that's just coincidence.)

When I was in the city (Biloxi, with a nice 50 MPH beach road), I drove over 90 miles and achieved about 50 MPG. The car was restarted countless times — yet only one recal.

On the way back up to WV I drove a bit more moderately (65-70, compared to, ahem, 75+ going down to MS) and got about 52 MPG. On the way down it was about 43, but MPG takes a noticeable toll when RPMs are constantly above 2500 no matter how well the battery's working.

Before the weather turned cold here in WV I was still getting 40ish in the city (stop-and-go, 25 MPH roads).

Now I'm getting 21-25. It seems that the regeneration part of the braking system rarely engages unless the car is very warm or I'm driving in S, giving me constant recals because it's obvious that the car just isn't charging the battery adequately.

And I think that might have been the problem all along: back when I was getting constant recals in nice weather, I couldn't recall the SOC ever going back up as if it was charging. All it would do is recal to full, then fall until it recalibrated again. The aged battery must be too deteriorated to get an adequate charge from what the system is programed to output.


It's comforting to know that there are some others with the same exact problem as me since I couldn't find any similar threads when I searched (and until today I didn't realize there was more than one post after an email I got for the first one).

So from my experience, I would suggest driving in S if you're in cold weather or if you're driving stop-and-go. At least S seems to charge the battery okay. But if you keep a constant speed of 45+ the engine drives the car more than the battery (as opposed to stop-and-go) and the recals aren't as noticeable in the car's power because of this.

 

Was this also happening for you before the last update?

Did you have to push Honda to get them to replace it on their dime? I see in your profile that yours is also a 2006, so I assume you hadn't driven more than 80,000 miles? I haven't taken my car in for this yet, but it's already at 90,000...

 

It was happening randomly before taking the car in. It's behaviour was different. Aproaching the freeway it would ran out of juice and will recalibrate while on the freeway.

Now it's every single time, withing the first couple of minutes of starting the car. I leave the driveway, make a left inmediately into the stree, then another left inmediately and it happens (2 minutes tops) I recorded it and it's posted on youtube.

My car has 60.000 miles, and I have Honda-doenst-care too. Useless. Even called Honda HQ and if the dealer says it's normal, Honda will not do anything.

As a side note, I've left my car parked for 4 days and on the 5th, I took it to work. It cranked up the engine with the 12v battery. Before I would leae the car parked a couple of weeks and it will still start up normally.

I've parked the car again for another 4 or 5 days to see if that ends up bringing up the darn light...

This is in Reseda, CA, weather does not go under 45-50 at night so it's not cold, and it's not hot.

If the car is doing this now, what will it do once we get back to 90-100 again?

I'm so dissapointed with Honda... I really wish the government finally catches them and this dirty software upgrade they did and hits them with millions of $$$, besides forcing them to replace all damaged batteries.

We are all paying or paid for the cars, some even paid for extended warranties. I have no reason to "baby" the car or change my driving habits as other sites sugest. My 2006 FEH has given me 0 trouble so far and no battery problems what so ever at the same mileage.

Juan S. Fernandez
2006 HCH <- crap
2006 FEH <- good