DTC P0505 Idle Control System Malfunction: Description

The idle speed is controlled by the ETCS (Electronic Throttle Control System). The ETCS is comprised of: 1) a one valve type throttle body; 2) a throttle actuator, which operates the throttle valve; 3) a Throttle Position (TP) sensor, which detects the opening angle of the throttle valve; 4) an Accelerator Pedal Position (APP) sensor, which detects the accelerator pedal position; and 5) the ECM (included in hybrid vehicle control ECU), which controls the ETCS. Based on the target idle speed, the ECM controls the throttle actuator to provide the proper throttle valve opening angle.