Drive Range, First Gear: Notes

As the vehicle speed increases, the transmission control module (TCM) receives input signals from the automatic transmission input and output speed sensors, throttle position sensor and other vehicle sensors to determine the precise moment to energize or "turn on" 1-2-3-5-7 control solenoid and command ON the normally-low 1-2-3-4-5 reverse boost solenoid and default control solenoid.