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Electronic Throttle Control System Description

Overview 

The electronic throttle control system (ETCS) opens and closes the throttle valve by electronic control. This system consists of a throttle actuator built into the throttle body, throttle valve and throttle position (TP) sensor A/B, accelerator pedal position (APP) sensor A/B, ETCS driver built into the powertrain control module (PCM), and ETCS control relay that supplies power to the ETCS driver.

ETCS is a system that opens and closes the throttle valve electronically, it has various functions such as:

Control 

When the accelerator pedal is operated, APP sensors are driven allowing the accelerator pedal position to be detected. The accelerator pedal position is delivered to the PCM, and the PCM drives the throttle actuator in the throttle body based on the delivered throttle pedal position to open or close the throttle valve. Throttle position is detected by the TP sensors in the throttle body and delivered to the PCM. The PCM drives the throttle actuator to control the throttle position during idling, during various system control, and when necessary, as well as based on the signals from the APP sensors.

For locations of each component on vehicle, refer to Component Location Index

GHH418180Courtesy of HONDA, U.S.A., INC.

Accelerator Pedal Module 

The accelerator pedal is equipped with a click point. Depending on the state of charge (SOC), if you depress more than the click point, the engine will start.