I have a 2012 jeep grand Cherokee overland and installed 2 12in subs about about a month and a half ago. Everything was fine at first, but then the alternator went out. (knew it was the alternator when i seen the smoke) So i ended up replacing the alternator. When i put the new alternator in the car would crank but not stay on for very long, and now it will not even crank. I've put jumper cables on and itll start with a jump, but as soon as you press the gas or use the A/C the car will almost instantly cut off.. The engine will sound almost like its boging out the just cut off. i have 2 Kicker subs with a 1000 watt AMP

Also I took the battery to advance auto, they said the battery was fine it just needed to be charged. My guess is the replacement alternator is bad, but would like a second opinion on it

 

With the later model Jeeps, there is a black box on the passenger firewall/fender, under the hood. This box contains pretty much all the fusable links for the electrical system. You might want to check there to see if any of the links (will look like a square fuse with a clear top) have blown/popped (you will be able to tell because they will look burnt or the metal strip inside is broken/not connected).

 

I know this is an old thread; however, our company specializes in this exact repair, with a 99% success rate for repair. The link for this vehicle is:

https://www.yps-usa.com/products/4753023041621

The repair title may be for a different Year/Make/Model; however, it is the same repair as long as the ECU is the same style. These units are damaged by the alternator failing and the alternator would need to be replaced, the wiring to the alternator checked, and then move forward with the repair. If the alternator is not replaced prior to installing a new ECU or repaired ECU, damage will occur again.

If anyone has any questions for us about this repair or misfire repairs, you can reach us here:

YourPartSource@hotmail.com

or our contact form here:

https://www.yps-usa.com/pages/83521863765