I just got a 2003 Honda Civic Hybrid. It wouldn't start because the battery was dead so I charged the 12V battery. I put it back in the vehicle, started it and drove it around a bit. What I noticed is that when I accelerate or brake the charge/discharge indicator is not showing anything. Anyone know why it doesn't show any progress or if it's even doing anything? Thanks.

 

If you have a multi meter you could check the battery voltage while the car is running and off. Voltage will be around 12.2V -12.7 V when off and running 13.7 +Volts. H

 

What will that tell me? It will be 13.7v because it's getting more from the "alternator"?

 

Yes. If it is not more when the car is running it means the alt. is not putting out! You may require a new converter in the IMA! H

 

Seems like the voltage is what you described so the alternator is working fine. Any other suggestions? I tried to pull the DTC codes (because check engine is on) but the reader cannot read the codes. Took it to Honda and they told me they can't read the codes either. What could be wrong?

 

If you have 13.7V or more going into the battery everything is normal. If the battery is not holding the charge you will need a new one. Check the battery in the morning and see if it has dropped below 12V . You could check it when you park it as well. That way you can see what you loose over night! These cars do not have a alternator they use a converter in the IMA system to reduce from 120 a/c to 12V D/C . Also remember it is a very small battery and draws down in a hurry if you are using it to power up a high amperage sound system. You may require a larger battery if that is the case. H

 

Battery seems to be fine. Here is something I noticed: I tried to read the DTC codes but the car could not detect the scanner (it would not read the codes). Also, electrical door lock did not work and the radio did not work. After driving the car for a while the radio and door locks started working. So I thought maybe there was just not enough power to let me scan the codes. I scanned it again and this time it gave me 3 codes. I think it won't read the codes if the battery does not have enough power. Just so if anyone has a similar problem. (even the dealer couldn't read the codes)

 

If you have to drive the car to build up the voltage for your radio and door locks to function then I would say your battery is week. Did you check the 12v strength after sitting over night. If it reads below 12v , change it. H

 

there is no alternator on a hybrid. connect a battery charger to the 12 volt battery to charge it.