Sierra 2500 2WD V8-6.0L VIN U (2004)
Electronic Throttle Control Module: Description and Operation
THROTTLE ACTUATOR CONTROL MODULE
The TAC module is the control center for the throttle actuator control system. The TAC system is self-diagnosing and provides diagnostic information to
the PCM through a dedicated serial data line. The TAC achieves throttle positioning by providing a pulse width modulated voltage to the TAC, as
directed by the PCM.