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Hello, sorry for the delay. Do you have a volt meter or testlight to check a couple things
well, do you want me to send the answer as I am rather confident it is or ? have you checked main powerf eed to the alternator?
Its not an answer in which you can simply try, The charging system is 100% computer controlled, The alternator really does very little. The PCm controsl all of it,. In the shop, I have to say, in past 20 years? most all Dodge/jeeps with charging problme wind up being the PCM,.It is very very common for the PCM to fail and prevent charging, You changed the alt, battery tested etc so,, I am sitting on about 98% you have a bad PCM, You can easily do an online search about Jeep PCm controlled alternators and will see many posts on this
I have attached the wiring diagram, It shows the PCM in the link of the charging system. Below is direct from the Jeep manual
SYSTEM OPERATIONThe charging system consists of:
The charging system is turned on and off with the ignition switch. When the ignition switch is turned to the ON position, battery voltage from the powertrain control module (PCM) is supplied to the generator rotor to produce a magnetic field. This is done through one of the two field terminals at the rear of generator. On Jeep models of previous years, battery voltage to this field terminal was supplied from the ASD relay.The amount of DC current produced by the generator is controlled by the EVR (field control) circuitry contained within the PCM. This circuitry is connected in series with the second rotor field terminal and ground.
Ok, There really is no testing for this, If you start testing at the back of the alternator, you run the risk of damaging the PCM even further. Its all about design and yes,, it has been a huge headache for many over the years,