I googled P1447 and it is indeed a bad pack warning! You may want to do this. Very interesting reading.

 

My car is running just as it was before the light came on, I'm thinking I'm going to wait it out and see how the car does. The battery shows no signs of degrading.

 

Yes I would wait as well. But google p1447 and you will be surprised with the # of hits you get. Hal

 

P1447 is listed in the '03-'04 HCH service manual as "Battery Module Deterioration". When you go from the chart listing to the page it references for that code, it says "Battery Module Deviation". (Not sure why there's a change in the wording, whether it's a typo or what.) When you go to the page that is referenced for that, it shows the procedure for a "Battery Module Replacement" where they replace the IMA battery.

I wonder if there's maybe one "stick" in the IMA battery that's bad enough to throw the code, and the others being fine, it makes your IMA light glow, yet the battery as a whole still functions well enough to manage to keep the car running as it is.

OgreKev has posted a link regarding the IMA battery which is very interesting:

http://www.hybrid-battery-repair.com/

 

A P1447 is a "Battery Degraded" and is similar to a P1433. What it means is that the available charge range of the battery has dropped below what the car considers usable. By charge range, I mean the difference in capacity between "full" and "empty" - or the amount of Milliamp-hours that the car can extract from the battery before it is forced to stop to avoid damaging it. This is a physical deterioration of the cells that can be reversed to some extent by dismantling the battery and reconditioning it. The problem is that you have one or more weak cells that are depleting faster than the rest and the car has to stop when ANY cell is empty no matter what the others contain. This causes a condition in the good (non-empty) cells that is similar to NiCad "memory effect". Finding and replacing the bad cells is key to a battery that will stay healthy.

If your car is still charging and giving assist, the process will continue and the capacity will continue to shrink until one of three things happens:

1. The car gives up completely and throws a P1433 error and stops all assist and regen.
2. The car manages to overheat one of the damaged cells and throws a P1449 error (at which time your car may no longer charge the 12V battery and will die when the 12V goes dead - similar to a dead alternator on a standard car)
3. You repair or replace your battery.

When you see your battery SOC charge suddenly drop down to zero over the course of a few seconds, that is called a downward recal. The car has detected an empty battery that it thought still had some charge (because the capacity has shrunk) and is recalibrating itself to try to find the new empty and full marks. When these happen at a rate of a few per day, the end is imminent.

I would guess that your battery gauge never goes up to full and seems to always be charging the battery. This results in a mileage drop of up to 20mpg on manual transmission Insights.

The good news is that when the car gives up on the battery and stops trying to charge it, your mileage goes back up.

The bad news is that you then have poor acceleration and poor city mpg, and you have a limited time (a month or two) before the car barfs and leaves you stranded.

 

My car is at 93.5k, light still off, I just got a tank at 47mpg. Weird?

 

It's become apparent that there are more than one failure mode. Some shut down the the DC-DC converter, some don't. I'm pretty sure that the shutdown is in relation to hard (constant) P1449 errors (which can be caused by a battery being driven down by the P1433 and overheating on charge), and soft (transient) P1449 errors which light the light to tell you that there was a problem at some point.

Your car may have now recalibrated to a point that it isn't deteriorating any more, so the P1433 isn't recurring. Your driving style may be such that you are putting no load on the IMA system at all, so it hasn't had to flex its' muscles and it has not detected the P1433.

BTW, I took a manual transmission 2003 HCH for a 20 mile test drive after a rebuilt battery was installed (10 miles highway out and 10 miles city back), and got 63 highway and 53 city. I'm used to driving an Insight, so I've got a light touch. On a second test drive, the lady who owned it got about 48 highway which was up from the 45 she had been getting. She'd had P1449 and P1433 errors.

 

This is great news, I'm now over 95k and the light has been off for about 5k miles. If the battery did recalibrate itself, do you think that it can remain healthy for another 100k? I live in Austin, TX and my drive to work is very flat. I don't go above 55 the whole way and temps are usually between 80-90. I'd really like to have this car for a long time, I love not having a car payment and getting great gas mileage. One other thing, for those of you still reading, on start up from acceleration, the car lurches slightly. It happens everytime, I haven't replace the CVT fluid in sometime, I hope that's it and I don't have a tranny problem.

 

Unfortunately, no. I suggest you drive it as long as you can and then reset the IMA system and try again. Keep doing this until the light won't stay out, then rebuild it.

 

I'm confused, do I need to reset the IMA system even though my IMA is off ? How would I reset it anyway? By rebuild, you mean replace? Sorry for my stupidity.