Hello there,
My issue is kind of complicated, but I'm posting here for opinions.

I have a 2000 Jeep Cherokee Sport 4.0
I have a 1100 Watt Amp with 10 inch Kicker Sub. (Set up is decent and got it new from a friend for present)
I have installed 240 Amp Alternator which I have had tested and is putting out 240 Amps
Installed Yellow Optima Battery
-750 CCa
870 CA

Also have aftermarket headlights
97-01 Jeep Cherokee Halo LED Projector Headlights

2 Hella Lights - which are around 200-250 Watts each

When I have all of this stuff turned on
INCLUDING
-Heater
- Rear Defrost
-Windshield Wipers

Then I hit my window swich my battery will begin moving from 13.7 Volts
to around 12.2 Volts

This is a large drop, any ideas as to why? Very confused as my friend has almost same set up and hitting his windows switches his Voltage only drops to about 13.4 Volts

Feedback Please

PS

I do not have a Capacitor on my Amp/ Sub setup Just ordered a 2 Farand one will be arriving 12/27

 

My condolences to the oncoming drivers

As long as it's <12V it's cool.

 

My dd is 100% completely stock. When I hit any window to roll it down I can see my lights dim. Not worried.

 

I'd suggest you institute the following system:

 

It seems that it would be a very rare occasion when all of these were on at the same time if at all in any real usage.


You did upgrade all wiring with the alt, big battery, and the amp?

 

Break out the volt meter and turn it all on. Get in there and check for voltage drops across all your major wires, the batt to the alt, the big ground to the batt, all the grounds,..bad connections are in play here. Batt terminals. Everywhere. Then drive down and have the charging system checked at autozone.

 

update?
try installing a volt gauge or ammeter to look for amp draw/voltage spikes