Recently installed voltmeter. During normal driving, the reading will oscilate between 14.3V~ to 12.3V~. Just read up on the charging system and apparently, the alternator contol system within the Ecm, changes the voltage generated at the alternator to improve fuel economy, depending on driving conditions.

Therefore my guage reading should be correct. Just want to check that others with voltmeters get approx. the same reading and that i dont have any problem with battery or alternator. Are you guys getting the same kind of voltage readings?

 

mine does the same thing its normal. it should do it with the car in gear and moving I think.

 

Same thing here. Alternator function is dependent on electrical load. If you start rolling up your windows at a stop while it's reading 12, it will jump to 14 and drag your engine down a bit when the alternator kicks on. When you're rolling, an RPM increase can cause it to engage, and otherwise it will engage periodically as a duty cycle to keep the battery charged.

It's normal. Freaked me out the first time I saw it too.

 

Yeah it did freak me when it happened. Good to know its normal. Thanks guys.