Throttle Actuator Control (TAC) Module

The throttle actuator control (TAC) module is the control center for the TAC system. The TAC module uses Read Only Memory (ROM) and Random Access Memory (RAM) along with an analog/digital (A/D) converter to control engine speed. The TAC module is self-diagnosing and communicates to the powertrain control module (PCM) with a dedicated serial data line. The TAC module receives accelerator pedal position (APP) sensor information from the PCM and provides diagnostic information to the PCM.

The APP sensor 1 enables the PCM to provide a target value to the TAC module in response to accelerator pedal movement. The TAC module achieves the correct throttle position by commanding the throttle control motor to position the throttle valve at the target value. The TAC module then compares the throttle position (TP) sensor 1 value to the target value. If necessary, the throttle control motor is moved slightly to obtain the exact desired position. The TAC module is not serviced separately and must be replaced with the throttle body assembly.