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).

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

	Idle Control Function
	Accelerator Control Function
	Fail-Safe Function
	Relationship Action with Other Systems

Control

When the accelerator pedal is operated, APP sensors are driven and the accelerator pedal position is 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.

Change of ETCS control (with ECON)

The ECON ON mode softens throttle valve control to reduce fuel consumption when the accelerator pedal is roughly depressed. Also, throttle opening becomes slow in comparison with the ECON OFF mode. However, if the accelerator pedal is depressed more than a certain level, control automatically becomes equivalent to the ECON OFF mode in order to ensure the acceleration.

Change of ETCS control (Type-R)

In the +R mode and the SPORT mode, the PCM varies the throttle valve opening characteristics. Accelerator response is improved by correcting the amount that the accelerator pedal is actually depressed by moving it in the throttle valve open direction.