No Radio & No HVAC controls after swapping enitre engine and wire harness from another truck

Ever Portillo · October 2, 2023

My Father bought a flooded 2018 Silverado and a wrecked 2017 Silverado. He took it to a shop to have all the working internals from the wrecked Silverado and put them in the flooded Silverado. We are talking engine, electrical and interior carpet,seats, etc. The truck runs and drives just fine but for whatever reason the Radio and HVAC controls do not work whatsoever. Ive checked all the fuses and reseated the plug connections, unplugged the battery and still nothing.

My research leads me to belive it might be the HMI unit. I tested the HMI on a 3rd 2018 Silverado and for obvious reason get the Theft Lock message. However when i put the HMI unit from the fully functional Silverado i get nothing on the display in the flooded vehicle. I even swapped the displays and HVAC controls and both are fully functional so its definetly not a display or control issue. Again I think its the HMI but i wouldnt even know where to begin to test it. i tried contacting the dealer but they have no idea what im talking about. My father took the truck to the dealer back in 2021 to have new keys made as well as diagnose it and they think its an issue with the ECU as they couldnt seem to program it. The only other option i can think of is sending the HMI and/or ECU to get it programmed/replaced but I wanted to reach out to yall here first and see if any of you have any tips/advice. Ive attached the diganosis from the dealer but they arent 100% certain.

Thank you!

PS ive also seen aftermarket radios for the silverado that look stock would those work or would the HMI still cause issues?