DTC P1128: Throttle Control Motor Circuit Shorted: Description
WARNING: This page is about a different car, the 2002 Nissan Maxima and 2002 Infiniti I35. However, it is still accessible from the selected car via links, so may be relevant.
The throttle control motor is operated by the ECM, and it opens and closes the throttle valve. The current opening angle of the throttle valve is detected by the Throttle Position (TP) sensor, and it provides feedback to the ECM to control the throttle control motor to make the throttle valve opening angle properly in response to driving condition.