Sometimes 12v charge light
 

Hello. I recently bought HCHII 2008. Sometimes after starting the engine constantly 12v LED lights up. After turning off and restarting it is already gone. What could be the reason for this? 12v battery to replace, DC-DC converter or something not connected to cable? Please help and greet.

Re: Sometimes 12v charge light
 

I am far more concerned with the other lights that are on.

7°C is relatively cold for NiMH, and you may be experiencing a restriction on 12V charging due to low temps.

When this happens, does the car start on the 12V system (cranks like a traditional car), or does it start with the IMA system?

Does this frequently happen more when it's cold, first thing in the morning, or all the time?

Honda does a poor job of maintaining it's 12V state of charge. You should first get the 12V checked for health. Remove it from the vehicle after 12+ hours of resting and take it to a parts store to do a load test. If it passes the first test, have them test it a couple more times. A marginal battery may pass a single load test, but poor health will start to show in tests 2 and 3.

If it's bad, I recommend replacing the 151R with a 51R - about 40% higher capacity. You will have to discard the plastic shroud pieces as they will not fit over the larger battery.

The first step in diagnosing any electrical/charging problem is to confirm the 12V is healthy with load testing.

Re: Sometimes 12v charge light
 

How can I recognize that the car run on 12V (cranks like a traditional car), or the start of the IMA system?

Now is the winter so it is not get too warm. There is no frosts but the temperature is in the range 1-8 Celsjus. This happened at different times of the day, but very rarely. The car does not have a garage. So he is always on the outside. I wonder if you connect the car to the computer to detect errors. Tomorrow i will test the battery charging 12V during load.

Re: Sometimes 12v charge light
 

When the car starts with the 12V, it sounds like a non-hybrid car. The engine "cranks" and starts. When the car starts with the IMA, there is no cranking, and the start is very smooth.

Re: Sometimes 12v charge light
 

So my car starts with the IMA system because it is very smooth. I tested the battery and 12V when the car is off the meter shows a 12.06 V when the engine working on N, it shows 14,23V. The car started with no problem. In ordinary cars with such a problem culprit is the alternator. In HCH2 alternator is not only the DC-DC converter. Perhaps something in him is failing. I also noticed a lot of dirt on poles 12v battery.

Re: Sometimes 12v charge light
 

Everything suggests your 12V is failing.

12.06 is a failing battery nearly depleted of charge. It should be over 12.6V after sitting overnight.

14.23V indicates the car is trying very hard to charge the battery. It is almost never this high except on a severely discharged battery.

Again, first step is to confirm health of the 12V. You have only confirmed that it is likely NOT healthy with both voltage readings.

It needs to be load tested. Personally, with the information you have provided, if the battery is > 2 years old, I would replace it with a 51R.

Re: Sometimes 12v charge light
 

I started the car and he had turned on the radio and ventilation. I changed course on N and showed me 14.23V. Recently I driving him on Sunday.

Re: Sometimes 12v charge light
 

I'm sorry. I don't understand what you are trying to say.

12.06V with car off = bad
14.23V with car running = bad

Load test 12V

Re: Sometimes 12v charge light
 

What should be the minimum results?

Re: Sometimes 12v charge light
 

I'm done. Good luck.