Altornator cutting out?

A week ago instead of reading 13 volts my volts would drop to 11.5 and my battery and E brake light would come on. It finaly went away 20 minutes later and the battery slowly charged up again. Now its doing it again and im worried my cars just not going to start one day or die out on me somewhere. The voltage still reads slighly lower than usual when the cars off. There is a lot of wiring for accessories on this car…all of which function perfectly. Im hoping to figure it out before it goes away and i have to worrie about it happening somewhere else away from home. What could i check to figure out if i have a battery, altornator or wiring issue? thanks

Start the car and take off the negative terminal of the battery, if the car shuts off, your alternator is gone. You can also take out your battery and get it tested, see how many CCA it’s storing. Or take the alternator into Part Source and have them test it for free. If both are fine, then you have a wiring issue.

Thanks Arslan!

Turns out the alt may be crapped out as the car wont stay running without the battery. The batt light only comes on when i 1st rev it above 1400rpm…then my relay for the alarm/starter starts ticking like crazy. When i start the car and not rev it at all and crank the stereo with lights and fans on the batt light wont come on…Very confusing and missleading…this problem just randomly started to happen so i hope its just the alt on its way out.