Transmission Control System Relay: Description and Operation

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

The powertrain control module supplies 12 volts on circuit K72. Circuit K72 connects to cavity C25 of the PCM. Circuit K72 connects to cavity C25 of the PCM. Circuit K72 powers the coil side of the electronic transmission relay The Powertrain Control Module (PCM) provides ground for the relay on circuit T30. Circuit T30 connects to cavity B30 of the PCM.

When the PCM grounds the relay the relay contacts connect circuit A14 from fuse 17/18 in the PDC to circuit T20. Circuit T20 powers the solenoids.