My cooling fans will not come on but I wired them direct and they both work does the temp sensor control the relays
Yes and no. There should be a sending unit for the cooling fans as well. Start by checking the fuse. Could be that simple.
All three fuses are good I checked them first was not sure how to check the 3 relays
Swap them with other ones in the fuse box that you know work. Like power window, rear defrost, headlight ect. If the windows , rear defrost and headlights don't work with the swapped relays then you know that the ones for the fans are no good.
Looking for a Used Avalanche in your area?
CarGurus has 5,229 nationwide Avalanche listings starting at $2,000.
Search Chevrolet Avalanche Questions
Chevrolet Avalanche Experts