Check for applicable trouble codes. To check codes, yourself, at the least you need an obd2 code reader will check manufacturer specific codes as well as po codes, see if anything for charging system. You have regulated voltage control, there are several modes with this system, the voltage output depends on the mode.
You could use a digital multi-meter at generator bat terminal, engine running, with a load turned on, what is the reading?
You can also, check battery amp draw, with everything off. That spec is usually very low, if too high, you have a battery drain. If the battery is down, you need to use a charger to charge it up. It is hard to do any testing with low battery.
If you put the meter leads across battery posts, everything off, the generic spec for a full charge is around 12.6 volts.
Tuesday, June 21st, 2016 AT 10:01 AM