Theory Of Operation

The transmission control output circuit is used to supply power to the Solenoid/Pressure Switch Assembly and the PCM when in normal operating mode and to turn off power to those components when a transmission "limp-in" mode is requested. The transmission control output circuit is also referred to as "switched battery". After a controller reset (ignition turned to the run position or after cranking the engine), the controller verifies proper control of the transmission control output circuit by monitoring the presence of voltage in each of the solenoid pressure switches and the Transmission Control Output circuits at the controller when in the disabled mode.