I have a 2004 GMC Sierra 5.3 Vortec. It came stock with a mechanical fan. Took that off and put in the electric fans from the 2005+. I want to control the fans with the ECU. I added the wires into the ECU in pin 42 on the blue connector and pin 33 on the green connector. Pin 42 triggers ground for Fan 1 and pin 33 triggers ground for Fan 2. In the VCM scanner software I can trigger these to come on with "Fan Low" for Fan 1 and "Fan High" for Fan 2. In VCM Editor it has on and off temps for each fan and the have been set and the fans are triggered on and off accordingly to what is in Editor.
The issue I am having is the fact that the ECU does not trigger either fan to come on when the A/C is turned on. Is there some other setting that I have to change in order for the ECU to trigger the fans to come on with the A/C.
Also, I want the fans to turn off after a certain mph. In Editor it has values that I can change but the ECU does not turn the fans off according to any of the speed values. There is a not in Editor that says "First Stage Fan Disable Speed: If AC is on, fan wil disable above this speed. If fan is on, it will disable above this speed if coolant is hot (V6 only)." Is this function really only available for V6?
So... Can I have the ECU trigger the fans when the A/C comes on and can I have the ECU disable the fans based on speed for the V8??? Any help on this would be greatly appreciated.