Secm (Load/Speed Management) - Daewoo G420E Service Manual

MI-04 SECM
(Load/Speed Management)
Drive by wire refers to the fact that the MI-04 control
system has no throttle cable from the Acceleration
Pedal (Figure 26) to the throttle body. Instead, the
SECM is electronically connected both to the
Acceleration Pedal assembly and the throttle body.
The SECM monitors the Acceleration Pedal position
and controls the throttle plate by driving a dc motor
connected to the throttle. The dc motor actuates the
throttle plate to correspond to the Acceleration Pedal
position when the operator depresses the pedal.
The use of electronic throttle control (ETC) ensures
that the engine only receives the correct amount of
throttle opening for any given situation, greatly
improving idle quality and drivability.
Figure 26
A Throttle Position Sensor (TPS), (Figure 27) which is
integral to the Drive By Wire (DBW) throttle assembly,
provides feedback for position control by monitoring
the exact position of the throttle valve.
Tier
G420E/G424E LP Engine
NOTE
The DV-E5 is not a serviceable assembly.
If the TPS sensor fails, the assembly
should be replaced.
Figure 27
Figure 28
SECM self-calibration and "cross checking" of the
TPS is accomplished by comparing the TPS signal to
a calculated throttle position in the SECM software
(Predicted TPS). In addition to the throttle position
sensor, a Temperature/Manifold Air Pressure Sensor
(TMAP) is used to monitor intake manifold
temperature and pressure (Figure 28). This enables
the SECM full control capabilities monitoring actual
airflow in relationship to desired airflow. The TMAP
sensor is a single unit incorporating both intake
manifold temperature and manifold pressure
measurement.
27 System Operational Overview