2018 Chevrolet Equinox 1.5 LT IOB Radio Wiring Diagram

Good day, Can someone help us find the factory wiring diagram pinout for the IOB, None Bose / None amplified Radio in the 2018 Equinox 1.5 LT FWD SUV. We have purchased the GMOS-LAN-10 wiring harness kit, AXSWC Steering wheel control unit from Axxess, and a Pioneer 2660NEX Radio head unit to completely replace the factory radio in the Equinox. How ever when we connected the Wiring harness and Radio to the 2 20pin connectors (located under the glove compartment), the radio will power on as normal, but will only play audio through the front speakers when reverse gear was selected (the backup camera does show on the head unit). We called a Tech at Axxess to help resolve the issue to no avail, as it is assumed to be a "plug and play" situation. We would like to obtain the factory wiring as it is, so when we choose to sell the Equinox, we can reconnect the factory radio back into the SUV, and remove the aftermarket head unit. If we can get both pinout diagram for both the Grey and Brown connectors.

The Equinox does have remote start, backup camera, Onstar (wish we do not use).