FWIW, I used a different code reader and got 5 codes:
1. POA78 $f10e, drive motor A inverter performance.
2. P15A5 $f10e manufacturer control.
3. CO3OO $f10e manufacturer control.
4. POA78 $f10epd drive motor A inverter performance.
5. P1440 $f10epd manufacturer control.

 

If your 12V is that flat, you need to get it on something > trickle charger - something around 4+ Amps.

I don't know if you meant to, but each description starts with "$f10e" which has no meaning to me.

"manufacturer control" implies they don't know what the code means.

Now is the time to get a subscription to the manuals and troubleshoot.

 

You are right. The trickle charger wasn't enough. I had to jump it again as I don't have a stronger charger. I took the car into the dealership this morning to diagnose all those codes.
I noticed the positive terminal cable is loose. Is there an easy, inexpensive fix for that, like a sleeve that can be put on the terminal?

 

Loosening the nut and then making sure the terminal is all the way down on the post might help.

This is an option:


Good luck at the stealership.

 

They want $700 to replace the cable. They won't do a sleeve. They want $180 just to tell me the cable needs to be replaced. They didn't even tell me what's wrong with the car.

 

I can only extended my condolences.

Given that this started as a flattened 12V issue, there's a remote chance that this is a contributing factor.

 

Not a good day. I had to jump the battery to take the car to the stealership. The stealership found the exact same codes I found with my $30 code reader. I declined their $700 offer to replace the terminal cable. They had to jump the car again when they returned it to me, and on the way home, the car displayed every dash warning light possible, and then slowly died on the fwy. I tried to jump it again on the side of the fwy, and it ran for a minute and died again. No power at all, not even the windows. I had to have it towed home. I'm at a loss for what to do next. Maybe buy a stronger charger and the shims and try to revive it that way?

 

You established that it's only charging at somewhat elevated rpm, i.e., 2000, so things are compromised, and unless you consciously stay at elevated rpm, you're not going to get charging. The loose cable compounds the issue. Honda charging algorithms suck too.

Disconnect it again and get the battery fully charged. You may also need to replace it as it's almost certainly damaged due to it being at a low state of charge and due to being charged at a trickle rate (slow charging encourages degradation). The deep discharge from the dome light also did a number on it. Keep in mind that every single second a battery sits at something below a full charge, it's being damaged. The lower the charge, the worse, and it's permanent.

Frankly, if this 12V is more than a year old, just replace the **** thing. I had a battery in my truck that tested good by every measure - on a load tester, on a digital load tester and via voltmeter. However, it wouldn't reliably start the **** truck. Solenoid would engage, but no crank 19 out of 20 times. Even installed a new starter. Tried swapping out the relay, manual starter terminals short, etc., nothing worked. Replaced the 12V, and it's started the last 50+ attempts. I felt like a joyous maniac repeatedly starting and killing the ignition in the driveway just to prove it wasn't a fluke.

Get a shim and replace the battery. Start over.

 

Will do. Got the shim already $3.49 at AutoZone. Thanks much!

 

Picked up a 2/10/50 amp battery charger/jumper at Harbor Freight for $60, charged the battery overnight as it is just over a year old, installed the shim and voila, it works! I took it for a 30-mile drive. The same 3 dash warning lights are still there, and the engine still won't shut down at a stop, but the car accelerates better, and the hard, clunking sound when the engine starts is gone. Progress!!! I'm going to see if I can get those sub codes later.