So where did that extra 1.5 Volts come from? Did the battery magically wake up? No, the alternator is an electrical generator and is supplying the voltage throughout your vehicle and kicked everything up to 13.5 volts. The alternator.
If you take your jeep
out for a drive using whatever Stock normal stuff like, the a/c, radio etc, then get home, park it and turn it off. Then a little while later, maybe a day or two, you get in and try to start it, and "click".
Now you check the battery and it reads 12v. Now you're sitting there thinking WTF?!!
You get out the cables and jump it..starts right up... = Bad Battery!
Moral of this story..The battery should have cranked with the battery reading 12v! In order for the battery to gain the additional 1.5v..the engine has to start! Otherwise..it would be "Magic".
RED, you yourself said.."If anything, the audio system will take away the current from charging your battery and make the charging process of your battery slower."
^This should't even be the case cuz the Alt, unless defective or too small (power wise), should compensate by throwing more power to the battery when needed.
Look, the whole Battery suggestion was based on what I said earlier, about the Jeep Batteries being know to crap out early. Most of which didn't even have any extra after market stuff putting a draw on them when the vehicle's off.
I know the ALT. provides power to everything while the vehicle is running and the Battery just cranks the vehicle, unless the vehicle isn't running. But if the Battery is crap, the ALT can try all day to recharge it, but it won't help.
All I'm sayin is people are putting extra stuff on their jeeps all of the time..Most of which won't be used often enough to really justify the cost.
But replacing something like a battery, that's proven
to be a POS on more than a few occasions, doesn't seem like a waste of $ in comparison. Especially if you're going to put MORE draw on that already crappy battery.
That being said: here's a 16 yo
who's putting a stereo in his jeep...You Just Know He's gonna play it whem the ignition is off.
Now take that into consideration, and add a battery known to be unreliable and see what'cha end up with. I'll tell ya.. Posting a thread on the JKO with a title that reads..Jeep won't start!
Now, What you guy's say IS true, when it come to a reliable, proven battery. That is, one w/out a poor history
If the alternator explanation is for me..I already know this.
The alternator was mentioned on another thread posted by the OP.
If it's for other people..GOOD INFORMATION!