Electronic Throttle Control Module: Description and Operation

Note: Refer to TSBs for additional information


Description

The Electronic Throttle System (ETS) control module and PCM receive sensor signal inputs (for instance, accel position sensor signal, throttle position sensor signal, etc.) and control the operation of the ETS motor and the limp home valve.

The ETS control module communicates with the PCM through CAN (Communication Area Network). When the engine control relay ON and the ETS relay ON, the ETS control module controls the ETS motor. The amount of the ETS motor movement is determined by the ETS control module and PCM according to sensor signal inputs.

The main advantages of the ETS:

- Precise control of the throttle plate in response to the driver's input.

- System integration with idle speed control, cruise control and traction control.

The main components of the ETS and their functions are:

1. Accelerator Pedal Position Sensor (APS): This sensor detects the driver's throttle input. This is a redundant sensor: two sensors in one housing.

2. ETS Control Module: This module controls the electric motor which controls the throttle valve. (2001-2004 XG3OO/350 only)

3. Throttle body with:

A. Redundant TPS (two sensors in one housing): This sensor detects the position of the throttle valve.

B. Electric Motor for controlling the throttle valve (3-phase, brushless, DC motor):
This motor directly controls the throttle valve opening angle.

C. Limp Home Valve: This valve allows the engine to continue running in case of certain ETS malfunctions.

IMPORTANT:

Whenever the ETS Control Module, PCM or Throttle Position Sensor is replaced or disconnected, the INITIALIZATION process must be carried out. If not, the ENGINE WILL NOT START!