Curious. IMA motors almost never need to be replaced. Sometimes a couple of sensors go bad. Perhaps they misdiagnosed but it's fixed because the sensor is replaced too.

Make 100% sure that you can see both the IMA and CEL lights when you turn ignition on, but prior to start. Bulbs burn out and they can be disconnected.

Not following on the firmware/resistor. If the resistor is the PTC bypass trick, you should have the old firmware. If it's something else, I don't know what it is.

Only charges at idle if car is low SoC or in a negative recalibration.

SoC showing consistently full (to the top) can indicate a failing battery as the car will adjust the state of charge upwards when it starts performing poorly at lower SoC.

SoC gauge is an approximation. Behavior is not always consistent even at same gauge reading. Temperature can affect it as well.

My gut says that everything that has been done is the minimum to get the car back to you without lights. I suspect all fixes are temporary. I hope not. I recommend you get yourself a decent ELM327 code reader so that you won't be at the mercy of shops/parts stores to read your codes when they return.

You can find PDF service manuals on eBay for about $40 IIRC. They are the same manuals Honda uses. This is not going to be a low maintenance vehicle, and the more empowered you are, the less it's going to hurt when you're getting screwed.

Good luck,

Steve

 

You're probably right but all I expected was something to run 18-24 months before needing an appreciable investment.
Figure a batt lasts 7 years, figure they replaced this battery in 2012, so this one is (hopefully) 4.5 years old. TBH I didn't expect to win this thing!
The mechanic was saying these cars are normally bulletproof and he was also surprised the IMA motor needed replacing.

I was thinking same thing, confirmed that IMA and CEL DO illuminate on bulb check.


SOC started in the middle, I had it moving between 45% and 80% somewhat predictably. I'll try to drain the IMA batt down to 2 bars tomorrow.
I wish I could find a dyno curve of a well functioning HCH-I and then get mine dyno tested. Figure torque output would be a decent judge of system status.
Normal to be getting assist to accelerate from 50-60mph even gently?

On your Gen 2 I don't know why they didn't just recal the gauge so that when its as low as the ECU wants to now let it go, it shows close to empty.

I'll def get a OBD2 reader. How do you feel about the bluetooth dongles and Torque app?

Seems like its running fine but I want to check the brakes and plugs (and maybe coils) tomorrow. Kinda surprised nobody sold and upgrade to this system. 26hp motor, a more densely packed and cooled 12 amp batt pack... too few potential buyers I guess.

Found my first surprise annoyance defect: Dome light stays on when door is shut unless you flip it to OFF. It does get dimmer when the door shuts but doesn't cut off.


Read entire owners manual (except seat belts, i read all that when i started driving) didn't find anything I was looking for: Dome light, or how to replace air filter (found youtube)

 

So Far So Good
3 hours in the car, about 80 miles, I knocked the battery down to 3 bars by not letting the brakes regen (shift to N and stop) it dipped down to 2 bars a minute later, then was charging no matter what I did until it hit 50%.
I then hit highway and let it sit at 50% until I got home where I could do alot of stops to recharge. Ended the run more or less around 80%.

Even braking gently and standing on the accelerator in gears far too high for the speed I was going (for max assist, max amount of time) didn't trigger any errors or do a good enough job to drain the battery, I had to resort to the tactics above.


Only thing I got left is to try and max out the SOC.....and see how many miles this first tank gets me... the gauge says 35mpg which would def be disappointing, my beat to hell 98 civic was getting that under normal driving 3-4 years ago.


I still haven't put the key on my ring yet, but I'm starting to think about it.

 

All good so far. Unfortunately, reconditions can frequently perform very well for a few weeks before they start to crap out. It just depends on the quality of the sticks and the process. If it lasts a month of normal driving, at a minimum, you're a good candidate for a grid charger. Plugging it in overnight every 2-3 months is probably not too burdensome.


A good diagnostic measure is to run it down to 3 bars but park it before it force charges. Let it sit overnight, pull the IPU cover and check the 10 tap voltages. If they're nice and tight (<0.2V = okay; <0.1V = better), then the pack may be in good shape for many months. Pulling it down to a low state of charge and letting it rest without charging will give you the greatest disparity.


Just know that reconditions are temporary. The chances of you dealing with a failed battery again in the next 12 months is extremely high. Watch for recalibrations. The first one you see is the start. It needs to be dealt with ASAP.


Steve

 

1 week later... so far so good. Crap I missed your last post Steve!

Battery sits 2-4 from full most of the time. I got it up to one from the top for a little while.

Grid only every 2-3 months wow, yeah thats not near as often as I had feared!

I ran it down to 3 bars and let it sit for 5 hours just as a maint thing before letting a 30 min trip get it back up to 95%.

I was planning on making that exercise a weekly thing to try and keep the battery chemistry in good shape. Thoughts?

 

Most in-car operations (20-80% SoC) only serve to deteriorate the cells, but at a dramatically lower rate than full cycles to 0% and 100%. The more batteries are cycled and the deeper they are cycled (higher charges, lower discharges), the faster they wear out. Period. Your plan will serve to wear the battery out faster.


Very small cycles and heat tend to induce voltage depression and capacity loss. THIS is what can be covered via manually cycling between true 0% and 100% SoC (grid charging and whole-pack discharging with light bulbs).


The best option for the driver is to just drive very conservatively trying to get the best mpg possible. The BCM will generally manage the battery better than the driver.

 

You got a fool on youtube then. though TBH i think he said he lets the "Hybrid Fan" run the pack down, then comes back 8 hours later to recharge it.

Also possible I was thinking of NiCD batteries which need to be killed dead to defeat memory.

 

There are fools everywhere.


All Nickel batteries get "memory". NiMH does as well, but it is dramatically more resistant to it.


If he is running the battery down in the car to within car limits, he's doing little to nothing.


"reconditioning" benefits from taking the cells out of their narrow operating range and cycling them through their entire SoC range to redistribute the electrolyte and restore the proper phases at the terminals.

 

S Keith, this post is INSANELY useful, thank you!
Had a CEL / IMA light come on and figured I would recondition the battery sticks by doing a stick recycle (sorry, haven't read your post on your thoughts about that yet). Took the battery out and, because I obviously know better than the YouTube video I was using, decided I'd remove the sticks from the non-Control Panel end. That meant I just ripped out the three temperature sensors. Only figured that out when I was putting the sticks back in. Had to make a decision on whether to try and rewire the tiny little temperature sensors (6 wires, three sensors) or just get a new harness instead. Decided on the new harness option, which came without what looked suspiciously like a resistor on one of the wires. Figured that a resistor could not possibly make that much difference!! Hahaha.
Still had the CEL/IMA lights when I was all done.
Took it to the dealer and was told (for $240) that I have a P1637 "replace MCM" code.
Reading this post, I now see that this all comes down, likely, to the **** resistor!!
I am going to splice in that resistor from my old hybrid battery harness tomorrow, and hopefully that is the "spoof it (install 20-30R resistor in the circuit to appear that the PTC is active on an older ECU)" issue that you mention above in this post.
Again, thank you!