Shift Solenoids

The shift solenoids are located in the valve body in the main case of the transmission. The TCM selects the required gear by controlling the appropriate solenoid. The following table indicates the solenoid control combinations which result in the 4 forward drive ranges:

1-2/3-4 Shift Solenoid:
D1 OFF
D2 ON
D3 ON
D4 OFF
2-3 Shift Solenoid:
D1 ON
D2 ON
D3 OFF
D4 OFF

The Shift Solenoids are supplied power via the Transmission Power Relay (internal to the TCM). The TCM controls the solenoids by grounding the appropriate control circuit via an internal solid state device called a driver.