Weird voltage drop

2007 jku sahara, 127k on it. Battery is a 2 year old autocraft (advance) platinum AGM and alternator was replaced at the same time. Recently, while driving the battery chime and light will come on. In preparation for the next time this happened I put my odb2 reader/torque app on the dash so I could monitor it. Starts up, reading at 14.3 (give or take) and then will at some point that seems random will drop to around 12.6. The most recent time I stopped w/o turning it off and threw a multimeter on the battery terminals. The reading matched what torque was saying. The most bizarre part of this to me is that I can restart the vehicle (even while rolling) and the problem resets itself to the mid 14's.

I'm completely at a loss as to what could cause this. No electrical changes to the jeep in the last few months other than unplugging the compressor.

rhino said:

2007 jku sahara, 127k on it. Recently, while driving the battery chime and light will come on. In preparation for the next time this happened I put my odb2 reader/torque app on the dash so I could monitor it. Starts up, reading at 14.3 (give or take) and then will at some point that seems random will drop to around 12.6. The most recent time I stopped w/o turning it off and threw a multimeter on the battery terminals. The reading matched what torque was saying. The most bizarre part of this to me is that I can restart the vehicle (even while rolling) and the problem resets itself to the mid 14's.

I'm completely at a loss as to what could cause this. No electrical changes to the jeep in the last few months other than unplugging the compressor.

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Sounds like the alternator is starting to go

Agreed, sounds like an alternator. Check connections first and check belt tension. Other than that, I can't think of anything else that would cause that.