Alternator or PCM

[NCJL]

The constant 8.5v when (disconnected from the Alt.)on the control wire told me the control wiring/connector was good. The only fluctuation with idle was when connected to Alt. with me applying movement.

The Alt output wire/stud voltage stays the same running or not with control wire disconnected or connected.
The only change in voltage from the Alt. Is with control wire connected with me applying movement/pressure. Only about a 1v fluctuation.
Internal control short inside Alt.
New Mopar Alt. On order.

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[Vtur]

Before you go and buy a new alternator. Check the decoupling pulley to see if it's bad. If you're not familiar, it's kinda like a spring loaded clutch pulley. It should turn freely in non-drive direction, but should have enough resistance in drive direction to drive the spindle. It'll reduced output if slight slipping.

Edit: what reading are you getting at the ouput stud at idle, and while reving?

 

[NCJL]

The output stud voltage does not change unless I apply pressure/wiggle the control wire connector. This also changes engine idle. The change is less than 1 volt.
No voltage change when control wire is disconnected from Alt.
I'm confidant the control signal issue is internal to the Alt. Not the wiring to the Alt.

 

[NCJL]

Replaced the Alternator yesterday. Confirmed Alt. was the issue.
About a 6 hour project. Changed the serpentine belt too, Just because…

 

[Gladstone]

About a 6 hour project.

Yikes, I'm not looking forward to this job eventually..

You thinking manufacture defect? Or environmental (water/mud/heat)?

Did you end up just using an OEM replacement or go aftermarket high amp? These smart alternators aren't cheap to begin with, some of the aftermarket high amps are crazy.

 

[NCJL]

Originally I ordered a PowerMaster Alt (the Saturday it started). The local parts guy and a few on line parts stores said it worked on the 3.0. Called PM Monday, told they did not have one for the 3.0. Returned.
Ordered the OE Mopar alt. Monday. Received Mopar alt Friday. Opened the box Saturday, to install, It was broken. One piece of paper used for packaging.
Wait till following Friday to receive replacement. Install Sunday 3/29.
The Mopar was $680 with shipping, tax and $70 core. Autozone could get a rebuilt for around $700.
Higher amperage doesn’t make sense without upgrading everything around it. At least to me.
Having all that time to think why the Alt went out….. I have an oil catch can installed. The drain is above the Alt. Thinking over time a few drops oil landed right on the Alt control module area.
I installed a Banks IDash about a year ago. The voltage readings on the IDash and Off-road pages was always different by about .6 volts. Talking to Banks tech a month ago, I mentioned this. He said they should be the same.
New Alt. The readings are the same. Thinking I’ve had an issue for a while. Probably oil drops.
I’m way better at draining the tablespoon of oil out of the catch can now versus when it was first installed.

 

[NCJL]

Another discovery. I’ve slowly been adding back in all the electrical devices.
The Auxiliary (not factory aux) battery had/has an internal short. Everything with it checks normal with battery charger and voltage meter. However under load (above 10 amps) the Negative cuts out.

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