STARLIFTER13

I have a 2016 1500 Silverado LT that has a weird problem I can't figure out. Truck was working great with no problems at all. Got up one morning and the truck wouldn't start. Voltmeter showed only about 10 volts and starter wouldn't turn over. I jump the truck no issues, it started right up and voltmeter showed it was charging at 14+ volts. Drove it all day on and off with no further problem. Next morning same thing, wouldn't start. Jumped it again. Volt meter showed it was charging up. Drove it onto work and voltmeter dropped to 10 volts. My buddy and I checked it out and alternator tested good on the meter along with the battery. But alternator was only putting out 1 amp and 12 volts. Had new alternator installed and garage checked battery and charging system out all checked good. Picked up the truck drove it home made a couple of stops, no issues. Got up the next morning again wouldn't start. Took it back to the shop once again. Shop checked it out again, everything checked good once again. This time they also replaced the battery. The battery that was replaced was new and only been in the truck for 4 months. I went to pick the truck up and it would not start again. Got the shop manager over and he said they check the entire system out, no codes, no parasitic drains, charging system, starter etc. checked out good. This time it would only start when it was placed in neutral and when it started the volt meter showed it charging, had a battery light, a message saying charging system problem and a message that said roll the driver's window up and down. Both of those messages kept repeating. Right now it is still sitting at the garage. Anyone got a idea or run into this before? The truck has 75k miles on it. Up until this problem the only problem it had was the AC condenser had to be changed due to cracks on the connection point.

Hokiefan

Sounds like the exact same issue I had with a 2017 Silverado except if mine wouldn't start I found out quite by accident that if I slammed the drivers door it would start but then would show all kinds of messages on the dash....Service 4 Wheel Drive.....Service Trailer Brakes....Service Stabili-Trak....you name it. Truck was in the shop no less than 6 times in 6 months. Dealer replaced....or said he replaced...the main wiring harness, checked battery and alternator....all to no avail. I got rid of that piece of junk. Hope you find your problem.