Auto Raiders

Has anyone had this issue? sorry for lengthy post but its all details that are odd. 2019 z71 LT issue free. Daily driver ~60 miles per day. All was normal, as I was pulling into a gas station, the truck dinged and gauge said service ESC, reduced engine power and shut off. didn’t think much of it because it happened as I pulled up to the pump. Filled up full tank, go to start it, and it cranks with no start. The starter and battery are strong, it cranks like normal, but no start. Thought it was fuel pump at first. Called the tow truck after 30 min of checking all fuses and disconnecting the battery for a few min. About an hour after multiple attempts of crank no start, tried to give it another shot and to my surprise it started but ran very rough. I immediately shut it off. Gave it 30 seconds and thought I’d try again. To my surprise again, fired right up, smooth as butter. No ticks, no rattles, no smoke, ran like normal. Gave it about another 5 min to idle beforere driving home, with no issues. Started driving home and after 15 min of driving, the truck dinged again, flashed service ESC, reduced engine power, and shut off. Pulled off on the side of the road and this time waited for tow truck. It did not start again no matter what i tried. When the tow truck brought it to the house, the driver wanted to put it in park, but accidentally held the brake and pushed to start and the truck fired right up. With no issues. Drove it off the tow truck and when I tried to move it 10 min later, it would do the same thing, crank no start. I scanned for codes and had 17 DTCs at first, once cleared, 9 DTCs remained with Ignition circuit issues. I went through all fuses and relays under the hood, driver side, and passenger side fuse boxes with multimeter and all tested good. Also tested relays with 12v power to each relay at pin 85 and 86 for an audible click. All tested good. What could be the issue? Was thinking a ground cable? I am open to your thoughts and ideas. Thank you in advance

Hello, just bought a 2019 Silverado LT Z71 and it threw a MIL B269A and B269C for Heater Coolant Pump Control Circuit Open and Heater Coolant Pump Control Circuit Low Voltage respectively. I have scoured the internet and youtube for a location but can't find anything. Can anyone help me and let me know where is this Coolant Pump located? Perhaps a connector is unplugged or a broken wire? It can also be a bad relay but I looked at all 3 fuse boxes (under hood, passenger, and driver sides) and I can't find any fuse/relay that remotely resembles Heater Coolant Pump. Does anyone know of the location for this relay or which relay this is tied into? Your help is much appreciated.