The right performance of the throttle body is largely determined by the position of the throttle plate. This is controlled by the Throttle Actuator Control (TAC) motors.
The Powertrain Control Module (PCM) controls the TAC Control system. For this purpose, it monitors the Throttle Position Sensor (TPS). In addition to monitoring the TPS sensor, it also determines the driver’s desired speed to give the appropriate response as required.
When the diagnostic code P2112 OBDII is stored, it means that the TAC system has a closed throttle plate. When this happens, air cannot enter the intake manifold system.