2019 Sierra sle 5.3
Saturday morning I pushed the start button on my truck and it just went "click", sounded like the starter engaged but not enough battery to turn over, I was in a hurry to get to an auction to ironically bid on a car hauler so I grabbed a different vehicle. Got out bid on the trailer, came home through a jump pack on the battery left it for about 20 minuets, truck started all seemed good, no warning lights no other symptoms. I drove down to a local pizza joint to pick up some wings and pizza out of habit turned the truck off when I got there, when I went to leave push button and "click". a guy I knew was there, tried to jump the truck, same thing "click", called wife, she came down with my good cables put them on for about 15 min and the truck pops off, down the road we go, about 1/2 mile from home dic says "service charging system, truck may stall" and it did. jumped it again, it stalls about 20 feet down the road, towed it home. Voltage on the battery measured 12.4vdc and stayed the same when I pushed the start button, put it on the charger at 50A for 30 min battery measured 13.6vdc, truck starts all looks normal. while its running I start to measure voltages, at the battery I measure 14.0vdc, at the alternator I measure 14vdc, from all points on the power distribution center on top the battery I measure 14.0vdc, about 20 min in it dies again. replace battery with fully charged battery, same story. Any suggestions?
sorry so long.