makes sense, so I disconnected the battery for 30 seconds, started again. The codes went away, but came again.
Now it reads P0404, P1559, P1570, P1571, P1600. I cleared the codes with the scan tool and now P1559 and P1600 came back.
The battery starts charging above 1200 RPM, the voltage goes up to 13.6V on the cigarette lighter adapter. I probably need to drive it longer for the voltage to rise to 14.4V.
Than I will repeat the disconnect procedure two more times.
Peter

 

Please set the scan tool aside. If you want to clear codes, use the 12V disconnect for the time being.

P1570 can prevent 12V charging.

1. Disconnect 12V battery for 30 seconds
2. Reconnect 12V battery
3. Start car and idle-charge the IMA battery until the charge indicator stops and the SoC gauge comes to a resting position.
4. Do not touch the throttle or any other controls. Your control of the car should be limited to turning the key and pressing the brake pedal as needed.
5. Ignore whether the 12V is charging or not.
6. Repeat 1-5 above a total of 3 times.

Once the above is complete, let the car sit for 30 minutes. Measure and record the tap voltages.

While you're waiting the 30 minutes, inspect the engine compartment for signs of frayed or chewed wiring. Additionally, locate and assess the ground straps - 1 to the battery and at least 2 to the engine/transmission. These can corrode with no visible indication and cause all kinds of issues.

Steve

 

ok, I completed the battery disconnect, start the car three times.
at the end after 30 minutes the 12V battery was sitting at 12.05V.
I noticed that the first time the car idled at 1500 RPM, turning the charge light off. 2nd and 3rd time it stayed at 1000 rpm with the charge light on. I think it was idling higher the first time because the engine was cold.
the ground connection on the battery was good. I found one on the transmission, that seams to end up somewhere under the batter, and could not find yet the 2nd one. i checked the connectivity with a ohm meter, that looked ok.

 

How did the IMA behave? Did it behave as I described? Is the IMA light still on?

 

the IMA light always came on again after about 2 seconds.

 

Did the IMA battery charge for several minutes and then terminate?

Do you have IMA function?

You you still get 12V charging at 1500rpm+

Lastly, what codes are now present?

 

no the IMA battery did not charge. After the engine starts running the IMA light goes on immediately, no IMA function.
the 12V battery charges above 1500 PRM fine.
the codes are P1559, P1570, P1570, P1571, P1600.

 

You noted a tap disparity on on the spare pack you installed. That is the likely source of the P1570, and it can also frequently inhibit normal 12V charging at idle and high rpm.

As far as the others are concerned, I don't have the manual. You can get a CD of the OEM manual on eBay for about $35. I think you're to that point.

 

thanks, maybe i can recharge the individual cells with an external power supply, once they are equal, the IMA might work. I probably have to remove the battery to do that?

Do these repair manuals contain decent schematics? That would help.
Tried to work on the P1559 code too, but could not located the correct sensors yet, maybe manual will help there too.
And there is a ABS light on as well...
thanks for the help

 

You would have to remove and partially disassemble the battery at a minimum. While the tap variations are definitely not good, I would expect some limited function for at least the idle charge period. It may be the other errors that are disabling IMA before it will even try to charge the battery.

The manual is the Honda Service manual. Wiring diagrams, schematics, component locations, etc., are all there to one degree or another.