8D–116
WIRING SYSTEM
QOS and EGR System (4JG2)
General Description
The circuit consists of the starter switch, QOS/EGR
control unit, glow relay, charge relay, fuel cut
solenoid, dropping resistor, thermo sensor, glow
indicator light (meter), glow plug, vehicle speed
sensor, tacho sensor, throttle position sensor, EVRV
and VSV; EGR.
The engine coolant temperature at the time of the
engine start-up is sensed by the thermo sensor to
change the glow time so that the optimum starting
conditions can always be obtained.
The idling speed just after the engine start-up can
also be placed in the most suitable conditions in
accordance with the coolant temperature by the
operation of the delay timer.
The indicator timer is activated upon the starter
switch turned to the ON position, and the indicator
light comes on for as much time as suitable for the
engine coolant temperature at the time of the
engine start-up.
EGR system controls the information of NOx by
returning a small amount of exhaust gas from the
intake manifold to the combustion chamber
through the EGR valve.