TAC Module
The TAC module is the control center for the electronic throttle system. The TAC module and the PCM communicate through a dedicated redundant serial data circuit. The TAC module and the PCM monitor the commanded throttle position and compare the commanded position to the actual throttle position. This is accomplished by monitoring the APP and the Throttle Position (TP) sensor. These 2 values must be within a calibrated value of each other or a DTC may be set. The TAC module also monitors each individual circuit of the TP sensor and the APP to verify proper operation. The TAC module commands the TAC motor to increase or decrease the engine RPM.