You sure the batteries are good on those cars? If they are original and the cars don't get driven much they may not hold a good charge.

These cars are very problematic when an unhealthy battery is present, if it was my car I'd replace the battery if it was original if not just for peace of mind.

You could always do the OBC test 9 I believe which checks alternator voltage as well, SlickGT1 had recent problems with an overvoltage which was solved by a new voltage regulator for a 100 bucks on his 4.8is.

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2018 Ram 2500 6.7L Cummins 68RFE
19k miles -Bright White/Black - Big Horn Sport - Crew Cab Short Bed
2013 X5 35D (CEO's) - Born on 5/17/2013 -
82k miles - Alpine White/Cinnamon Brown/Premium Pkg, Sport Activity/Premium Pkg and Sound/20" Style 214/Running Boards