Could use some help on a 2004 Silverado fan question
I have a 2004 Silverado and replaced the 28" Radiator with a 34" unit and added the OEM electric fans
from a 2005+ Silverado. I then paid for a tune from an unnamed source that would activate them via
a Nelson 05+ OEM fan harness and the 2 pins on the PCM. The fans do not come on and the high
speed trigger on the PCM seems to not be turned on as I get no ground from it when it should be
triggering. I get a single low speed fan based on coolant temp but nothing with the AC.
Can any one tell me what it is specifically one must do to get the fans running with the coolant temp
and the AC pressure? I am just about to the point of getting a Flash Scan and Tune and fixing it
myself. I am far from a tuner but I have a backup PCM and am willing to give it a shot.