I have a 2017 Accord 2.4L, and the message on the dash read, "Check Charging System". I get my multimeter and check the battery which is 1 year old, and I get 14.4v while running. The next day I check the voltage before starting, and it says 12.8v. I take the car to the Honda dealer to have the battery checked out to see if by any chance its not holding a charge. They test the battery for 2 hours and said the battery is fine. Battery is good, the alternator is good, so the only other thing it could be is the battery sensor on the negative terminal at the battery. I replaced the sensor with a Honda OEM part, then cleared the code. Everything is good again.

 

Update:
Message is back on. Charging system checks out good. New battery senor put in and still the same message on the dash after clearing the code P154A. Could it be the ECU? Any suggestions would be helpful. Thanks.

 

check fuse #20 it should be a 7.5amp in the under hood fuse box

 

Did you resolve this issue?

 

No it did not resolve the issue. I installed LED interior bulbs, and the dome light was blowing the #20 7.5A fuse. I had to take the car to the Honda dealer since I did not know what all was on that circuit. They said the interior lights are on that same circuit. I put the OEM bulb back in and it fixed the problem. Now the question remains, was the battery sensor even bad?