Well, this car has had me pretty darn frustrated for the past month, so first let me give a little background.

I bought the car late March from a used auto dealer in PA (120 miles from me), a friend of mine has an 05 HCH-I and he loves it as do I; so I decided to pick one up. Got approved for the loan, bought it, loved it. I got 30 miles outside of the dealer after I purchased the car and the IMA/Check engine light came on. So I got home, read the codes, same two codes that every IMA battery failure throws (after a few minutes of research on google). I contacted the dealer and after a week of them throwing me a load of crap they finally caved and said they would fix it.
I gave the car back, they put in another battery, I was a happy guy. Until I got ONLY TWO MILES from the dealer and the same lights came on. I immediately turned around, called the dealer, told him to fix it right this time. I also told them to actually test drive the car since they clearly didn't before.
Now three weeks after I bought the car they're finally done (mind you, I've now driven close to a thousand miles over this crap, I'm sure you can sense my frustration). I drive home, no lights, no issues with the IMA, getting low 50's for gas mileage, I'm a happy camper.
I noticed through driving that every now and again the charging/assist and IMA level would act weird, figured it was because of a new battery, maybe it needed to learn or calibrate so I kept driving. Fast forward to present day (Two days after temp tags have expired) I notice that on start up the IMA & Check engine light don't illuminate, RED FLAG.
So I pulled out my code reader and was confronted with six codes.

• P1435 - HYB - Charge/Discharge Balance Problem - CURRENT
• P1433 - HYB - Battery Module Deterioriation - CURRENT
• P1600 - ENG - Integrated Motor Assist System Malfunction - CURRENT
• P1601 - ENG - Integrated Motor Assis System Malfunction Without Malfunction Indicator Lamp - CURRENT
• P1600 - MOD - Integrated Motor Assist System Malfunction - CONFIRMED
• P1433 - MOD - Battery Module Deterioriation - CONFIRMED

Let me describe how exactly this thing behaves when it acts up. I'll be driving, happy and dandy, singing my favorite song, getting some sweet assist from the hybrid motor like normal, and then out of nowhere it will stop assisting. The system will charge (about 20-25%) under throttle less than 50%. So as I'm giving it gas it charges. Any throttle greater than 50% in doesn't show charge or assist (This has been tested in 4th & 5th gear at 40-80mph on multiple occasions). It essentially behaves as if the battery is reading 0% and needs to be charged. However, the battery guage, when this happens, will start at full when it was working properly, and rapidly drop even when there is no assist. This condition normally last for a minute or two, and once it kicks out of this mode the battery gauge will fill back up from 0 (or whereever it stopped "draining") to full in less than a minute. It's almost like a sensor for the battery percentage is going haywire.

This issue didn't happen before the battery was replaced, and doesn't happen under any specific condition other than just driving normally.

I'd also like to add that I know my way fairly well around these giant hunks of metal, but it is the dealers responsibility to sell me a working car when it was advertised as such.

Cliffnotes:
Bought an 04 HCH, found out the IMA battery was toast, had it replaced, that one was toast, had it replaced again, now it's having a charge issue. Charges under <50% throttle, doesn't assist >50% throttle. This condition only lasts a minute or so. IMA gauge goes to empty under this condition, back up to full when it steps out of this condition. Scanner is pulling 6 codes listed above.

Any help is greatly appreciated.

 

Thank you for the TL;DR. I almost moved on.

You're describing recalibrations. An occasional recal happens on a good pack. Daily recals happen on a significantly deteriorated pack.

Bottom line. The 2nd replacement pack is better than the 1st but not by much.

I suspect they've been replacing the battery with used spares to try and save cost... and all Honda replacement packs can contain used cells.

Back to the dealer you go for your 4th battery...

Steve

 

Update: since the check engine and IMA lights weren't illuminating on start and I got 6 codes, I took it upon myself to disassemble the gauge cluster. The IMA and check engine light were removed.

 

Wow.

 

Update: I called the service advisor at Honda who worked on my car when it was in their hands. The write up is for diagnostic which resulted in a bad IMA battery diagnosis. I asked him about the lights being removed, he said he'd have nothing to do with that.
I did a little bit of research on the repercussions of doing this and it is considered fraudulent concealment which is illegal. I plan on giving the dealer three options.

Refund me the full price of the car and I will keep it as well as fix the problems on my own accord.
I will take the car to a Honda dealership and send him the bill for the damage caused to the gauge cluster as well as fixing the original issue.
I will see him in court.

 

FYI, Dealer refers to the establishment that I purchased the car from, which is NOT Honda.

 

Personally, I'd demand a refund and walk away.

Them refunding your purchase price AND letting you keep the car under threat of reporting them has a whiff of blackmail about it. If you're going to report them, you should just do it. There are compensatory provisions, so you could probably get your option #2 just by reporting them, but it would be a big hassle.

This car has been nothing but a headache for you. It's 10 years old and you can be certain that any HCH1 that's not running a recently replaced battery (preferably aftermarket) WILL have an IMA battery issue in short order.

Good luck,

Steve