Circuit/System Description
WARNING: This page is about a different car, the 2009 GMC Sierra, 2009 GMC Cab & Chassis Sierra, 2009 Chevrolet Silverado, and 2009 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.
The transmission control module (TCM) high side driver 1 is located inside of the control solenoid (w/body and TCM) valve assembly and has no seviceable parts. The high side driver 1 provides the voltage for the TCM pressure control solenoids and shift solenoids. This fault is handled inside the TCM and no external circuits are involved.