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Fluid Pressure Sensor/Switch: Description and Operation

CIRCUIT OPERATION
The Solenoid and Pressure Switch assembly, located in the transmission, is used to control the shifting of the transmission. Power for the assembly is provided on circuit T16 from the transmission control relay. The Transmission Control Module (TCM) provides the ground path for the various solenoids depending on operating conditions. This assembly is also case grounded to the transmission. The case ground supplies the ground path for the pressure switches.

The following circuits are controlled by the TCM for the Solenoid and Pressure Switch Assembly.
- T20- Low/Reverse solenoid
- T19- 2/4 solenoid
- T6O- Overdrive solenoid
- T59- Underdrive Pressure Switch
- T50- Low/Reverse pressure switch
- T47- Kick down pressure switch
- T9- Overdrive pressure switch
Circuits T9, T47, and T50 are switch inputs to the TCM.