Battery crash / no regen braking??
 

Hi all,

Been lurking about for awhile... We've been experiencing a condition with our 06 HCHII that I haven't seen exactly mentioned in other threads. My apologies if it's been discussed.

So... hot weather, A/C on. Engine at operating temp. Everything's fine, coasting & braking are regenerating, battery isn't fully charged.

Suddenly, battery SOC is nosediving. I know some have posted about a "recalibration", but what I haven't seen mentioned is that during this nosedive to zero, the braking regeneration is not working. I know because (1) the green bars don't activate during braking, and (2) the car doesn't stop as fast - the stopping is like first thing in the a.m. when you don't have regen either.

After SOC hits rock bottom, the car goes into fast idle and recharges some. Eventually regen braking returns, and the battery SOC comes back up.

This has been happening pretty regularly this summer. I'm fine with this if it's normal. The thing that had me puzzled was that the regen was disabled. Maybe that's just part of the recalibration process...

Thanks in advance for any clarity,

Steve

Re: Battery crash / no regen braking??
 

yes it is. stop riding the pack.

Re: Battery crash / no regen braking??
 

That was a little sharp wasn't it?

I have the same issue, and while it is theoretically "normal," I do not think having it happen frequently IS normal. How often does this occur for you Jettage? For me, at first it happened very infrequently, and then has started happening with much greater frequency. I'm up to the point where it is happening at least once, often twice a week.

While theoretically, it is made worse by higher temps, it happens more often for me in the morning when temps are in the mid 60s than on the way home when temps are in the high 80s. It was happening at least once a month even in the winter. I don't use the A/C, and I make an effort to stay off the Asst as much as possible.

I have been meaning to take my car in to the dealer, but I have had too much going on to get there. I am fully expecting a "we drove it but couldn't reproduce it--it is a normal event" but at least I will have it documented.

Re: Battery crash / no regen braking??
 

Hi Kristian,

I'd guess it's happening weekly. I did call my dealer today & he searched for any TSB's or updates that would relate to this issue, but came up empty. He also said that he didn't recall any similar issues coming thru their shop. Of course, I can bring it in, but as he said, it probably won't do it while they have it there.

He did suggest that if the A/C is on when it next happens, try turning it off & see if things change. I think I will also try shifting into "S" to see if that triggers anything.

If the entire process (no regen included) is a standard routine (related to "recalibration", or something else), I am very curious to know what conditions trigger it... It almost feels like once the computer(s) decide to go into this mode, it locks out regen to ensure that the battery SOC goes all the way down to zero as part of the process...

I need to do some more forum & internet trolling - see if anything turns up.

Steve

Re: Battery crash / no regen braking??
 

Yes, this happens to me too. The ironic thing is that I can usually spot the recallibration before it happens because it will light up two green bars of charge and stay there, even though I can feel that the car is not doing any regen (zero resistance slowing me down). It will stay with the two bars, even if I apply the brake or give more/less gas, and then the SoC will drop like a lead balloon.

I don't have any doubt that this is a designed process that happens when certain conditions are met. What I want to understand is why these conditions seem to happen so frequently when I minimize battery use, don't use A/C, and don't live in an environment with extreme heat. Also, since it happens so frequently and since it does seem to drop the battery to zero, what is the long term harm in this happening weekly.

Are there a lot of hills in your normal driving? Do you use the glide frequently? Those are two things that pretty much define my commute--lots of hills and I glide (no Asst) about 90% of the time on downhills.

Re: Battery crash / no regen braking??
 

That's exactly what happened to me...

No our commuting is a mix of highway and in-city, usually returning low 40's mpg. I'd say "average" hills / glides (less than San Francisco, more than Kansas!). We do use the A/C, spendthrifts that we are (but 90's and humid will make the strongest person crack). We're not hypermilers by any stretch, but have somewhat altered our habits in favor of the hybrid.

Re: Battery crash / no regen braking??
 

It may give you more problems if you don't use the air. Battery's require cooling like we do! I have had this happen once in a about 18 mths. and it was a cool day. So go figure! Have you had you back-up starting battery checked for strength? Mine has never had to start the car but apparantly it is important too how the car will function. Something you could check out without difficulty. H

Re: Battery crash / no regen braking??
 

I've had this happen, but only once or twice. And only without outside temps like 105 or higher with the AC on. I've heard the system is designed not to attempt to charge the battery when ambient temperature gets that hot.

MPG drops like a rock when it happens

Re: Battery crash / no regen braking??
 

I used to have it happen once a week until I started using the Auto A/C instead of regular A/C. Now I can't remember the last time it's happened.

Re: Battery crash / no regen braking??
 

Jess, that is a good point. I use auto A/C as well.Worht a try anyway.H:angel: