Hello,
I have a 2002 Sierra 4X4 5.3.---- tuned by Allen.
Question is- does and at what temperature does the PCM red pin #33 activate?
Also Blue pin #42?
I am going to wire up a two speed electric fan and would like to use pin #33 to control one of the fan speeds, though a relays of course.
Is this active in the stock 2002 PCM? Or does it have to be tuned to work?
Thanks