Replaced my battery today in my wife’s Macan S with a Interstate MTX-49/H8 battery. All went well and I was able to program the vehicle with an Autel device. My battery was just two months under 6 years so I feel like I got good use out of it. My question is that when I tested the new battery in the Macan before starting the engine, the voltage accross the posts was 12.1 volts. It is a new battery. My question is do you think that this battery was charged properly from the factory or is that the way they come. I have driven it and it showed 14.7 volts on the dash while driving. I’ve got it on a trickle charger tonight so I’ll check again tomorrow.

Anyone have an idea on what the typical voltage for a new AGM battery is? Thanks

 

Keep in mind batteries are properly charged before leaving the manufacture and typically sit in a warehouse for X number of days, including at stores, etc. Look at your manufacture date stamped on the battery. Put it on a battery charger and/or drive your vehicle, 14.7 VDC is normal.

 

Thanks

 

About 12.9V for a fully charged battery that is disconnected and therefore with no load on it.

 

Thank you

 

 

That 14.7 volts you're reading from the voltmeter while driving is from the alternator, not the battery. The battery will always be somewhere around 12volts. The alternator pushes 14.3-14.9 to charge the battery.

 

I agree with this

 

You really think? Why, have you taken some measurements? LOL

 

A bit under 13v is normal with car not running. 14.7ish while car is running is normal. At least for 991.2. Check voltage with car off after taking some longer drives. If you are at 12v on a new battery, something is wrong.

 

By the way, the on-board 991 voltmeter is dead accurate to within 0.1V (digital meter: +1 count) as I checked the actual battery voltage with my Fluke DMM.

 

Your attempt at sarcasm is elementary at best. I owned a mechanics shop for a bunch of years...so, yes. I've taken many "measurements".

 

Well you obviously do not know much about batteries. Do you get 16 years out of your battery? I highly doubt it. What is the name of the shop.