Page 241 - Foton Workshop Manual - Aumark (BJ1099)

ENGINE CONTROL SYSTEM - ELECTRONIC THROTTLE 11-15
ELECTRONIC THROTTLE

1. Principle of Work
The throttle opening of electronic throttle body assembly is obtained that according
to throttle pedal control input signal controlled by the driver and other various
sensors' input signal, ECM calculates the engine output power required by the
vehicle at this moment and in this state, and then accordingly it controls the fuel
supply (injection) quantity of the engine, so as to ensure the engine works in the
best control condition. Electronic throttle body is added with the components of drive 11
motor, gear drive mechanism, etc. as well as throttle position sensor with stronger
function and reliability.
2. Function and installation
The electronic throttle body is composed of three parts of DC motor, throttle position
sensor and throttle. It is equipped on the intake manifold to receive the signals from
ECU under all working conditions, comprehensively process and adjust the throttle
opening, meanwhile it measures the throttle opening in real time through throttle
position sensor and feed back to ECU, so as to achieve the goal of meeting air
intake demand of engine under different working conditions.
3. Working temperature range:-40℃ ~140℃
4. Sensor power supply voltage:5±0.2V
5. DC Motor:
Voltage range:8V~16V
Terminating resistor:1.1Ω~2.1Ω
Inductance(1kHz):1.1±0.3mH
6. Fault phenomenon and judgment method
(a). Fault phenomenon: unstable idle speed, poor acceleration, etc..
(b). General causes for faults: Man-made fault (such as damage to casing).
(c). Precautions for maintenance: avoid the occurrence of falling or knocking, pay
attention to installation position, in consideration of leakage in the shaft seal
of throttle after long-time running, the throttle body assembly shall be installed
according to the correct position and direction, the maximum allowable moment of
fastening screw is 10N•m.

Page 241