DTC P1122: Electronic Throttle Control Circuit: Description
WARNING: This page is about a different car, the 2003 Infiniti G35. However, it is still accessible from the selected car via links, so may be relevant.
Electric throttle control actuator consists of a throttle control motor, Throttle Position (TP) sensor, etc. Throttle control motor is operated by ECM and opens and closes the throttle valve. Current opening angle of throttle valve is detected by TP sensor and provides feedback to ECM, to control the throttle control motor to make throttle valve opening angle correct in response to driving conditions.