Transmission Control System Relay: Description and Operation

CIRCUIT OPERATION
The transmission control relay powers the overdrive solenoid, torque convertor clutch solenoid, and variable force solenoid. All three solenoids are molded together.

When the ignition switch is in the START or RUN positions, it connects circuit A1 from fuse 8 in the Power Distribution Center (PDC) to circuit A21. Circuit A21 powers circuit F99 through fuse 18 in the PDC. Circuit F99 powers the coil side of the electronic transmission relay The Powertrain Control Module (PCM) provides ground for the relay on circuit T66. Circuit T66 connects to cavity B3O of the PCM.

When the PCM grounds the relay, the relay contacts connect circuit F92 from fuse 17 in the PDC to circuit T20. Circuit T20 powers the solenoids.