Hey all, I have read through many, many long threads on the IMA batteries but haven't seen the exact scenario that we are dealing with, so I thought I'd ask and hopefully get some feedback.

Ok-- background 2003 hybrid, bought brand new in NH by my mom's inlaws. They put 12k miles on it (over about 4 years) and then my mom and stepdad inherited the vehicle. Brought to AL. Mom drove it for a few years and then the battery was replaced (at 7yrs) Car now has about 95k miles on it and has been meticulously maintained at the dealer. Mom only drives it to and from work (about 40 miles per day, 5 days a week). Otherwise they drive another vehicle.

Now for the issue-- Over Thanksgiving break the car sat or about 5 days, and when it was cranked again the IMA light came on. They took it in to the dealer and they told them the battery was starting to go, but it was fine to drive. She drove it from then until Christmas break. Over Christmas it sat or 10 days without being driven. It cranked but was sluggish. She left home and got about 5 miles on the interstate before losing all power, including power steering. Thankfully she was able to coast off the interstate safely. She went and bought a new car that afternoon, and now the Hybrid is just sitting at her house. oh, the new battery that the dealer replaced is right around 3 yrs old and the 12v was replaced last year.

My questions are these-- 1) could the battery issue be caused by sitting? 2)Is it something that could be reversible or is it permanent? 3) Is the IMA battery completely dead (ie has to be replaced before the vehicle can be driven?) 4) I feel like this is a huge safety issue that should be pursued with the dealer-- what say you? 5)Is the car safe to drive or is there a way to make it safe? She has offered to give the vehicle to me if I want to deal with the issues. If the only recourse is to put a 3k battery in, then it doesn't really seem worthwhile, but if there are other options, then it is a great car that has been incredibly well maintained.

Thanks in advance or your assistance!

 

1) Yes, but that's probably not the main cause.
2) No, Yes, but it could be mitigated with a grid charger.
3) Probably not.
4) Good luck with that. You are only the 238,574th person to have an IMA battery go out. Maybe somebody will flag it as a safety issue.
5) It depends. Yes.

Elaboration: Without checking the codes, it's impossible to say what the issue is. The "sluggish" issue you describe is more indicative of a 12V battery issue or DC-DC converter issue. The RED battery light will come on when the 12V isn't charging properly.

The IMA battery was likely not "NEW" when replaced 3 years ago. The general consensus is that the Honda replacement packs contain a mix of new and refurbished sticks, so 3 years is a decent run for a pack that likely contains refurbed sticks.

Just because the 12V is a year old, doesn't mean it won't go bad.

Suggestions:

1) troubleshoot the "sluggish" issue. Read codes and report back.
2) get a grid charger to "balance" the pack and potentially restore IMA function.
3) bypass IMA. IMA can be disabled and can operate like this safely indefinitely, but the 12V will only charge between 1500 and 3500 rpm - which is typical operating speeds. Extended idling can drain the 12V in this instance.
4) Quality aftermarket batteries can be had in the $1700-2200 price range. These contain quality new sticks of higher capacity. The car is low mileage and likely has another 150,000+ miles in it, and a new battery is probably worth the investment if the other options don't work for you.

When bypassed, you avoid the IMA system initiating forced regens to recharge the battery. These regens hurt mileage significantly. When bypassed, the car becomes a very efficient 1.3L car and can easily get highway miles in the high 40's. Mixed driving mileage won't be as good as a fully operational IMA system, but it's way better than the car constantly trying to recharge the battery with a partially functional IMA system.

Good luck!

Steve