Circuit Description
WARNING: This page is about a different car, the 2006 Pontiac Montana SV6, 2006 Chevrolet Uplander, and 2006 Buick Terraza. However, it is still accessible from the selected car via links, so may be relevant.
The pressure control (PC) solenoid valve is located in the valve body. The PC solenoid valve controls transmission line pressure based on current flow through its windings. The TCM determines desired line pressure based on throttle position and other inputs. The TCM then varies the duty cycle on the high side of the PC solenoid valve to control current flow to the solenoid. Current is controlled from about 0.02 amps for maximum line pressure to 1.1 amps for minimum line pressure. The TCM monitors the actual current to the solenoid.
If the TCM detects a commanded current draw that differs from the actual current draw by more than a calibrated value, then DTC P0961 sets. DTC P0961 is a type C DTC.