Daewoo G420E Service Manual page 17

The SECM makes any necessary corrections to the air fuel ratio by controlling the inlet fuel pressure to the air/fuel
mixer by modulating the fuel trim valve (FTV) connected to the regulator. Reducing the fuel pressure leans the
air/fuel mixture and increasing the fuel pressure enriches the air/fuel mixture. To calculate any necessary
corrections to the air fuel ratio, the SECM uses a number of different sensors to gain information about the engines
performance. Engine speed is monitored by the SECM through a variable reluctance (VR) sensor. Intake manifold
air temperature and absolute pressure is monitored with a (TMAP) sensor. The MI-04 is a drive by wire (DBW)
system connecting the accelerator pedal to the electronic throttle through the electrical harness, mechanical
cables are not used. A throttle position sensor (TPS) monitors throttle position in relation to the accelerator pedal
position sensor (APP) feedback. Even engine coolant temperature is monitored by the SECM. The SECM
controller has full adaptive learning capabilities, allowing it to adapt control function as operating conditions change.
Factors such as ambient temperature, fuel variations, ignition component wear, clogged air filter, and other
operating variables are compensated.
Open Loop LP Fuel System
Fuel
Lock-Off Converter
MI-04 Closed Loop LP Fuel System
Coolant
Sensor
Acceleration
pedal
Angle
Oxygen
Sensor
Sensor
Fuel
Lock-Off Converter
Tier
G420E/G424E
LP LP
Mixer
G420/G424 Open Loop LP Fuel System
VR
Sensor
TMAP
Sensor
Fuel Trim
Valve
LP LP
Mixer
G420E/G424E Closed Loop LP Fuel System
LP Engine
Governor
Small
Engine
Control
Module
(SECM)
Electronic
Throttle
16
Engine
Muffler
Smart Coil
Catalytic
Engine
Muffler
System Operational Overview