Nissan Silvia. Manual - part 172
System Description
NMEC0777
Sensor
Input Signal to ECM
ECM func-
tion
Actuator
Camshaft position sensor
Engine speed
Fuel pump
control
Fuel pump relay
Ignition switch
Ignition signal and start signal
The ECM activates the fuel pump for several seconds after the ignition switch is turned on to improve engine
startability. If the ECM receives a 180° signal from the camshaft position sensor, it knows that the engine is
rotating, and causes the pump to perform. If the 180° signal is not received when the ignition switch is on, the
engine stalls. The ECM stops pump operation and prevents battery discharging, thereby improving safety. The
ECM does not directly drive the fuel pump. It controls the ON/OFF fuel pump relay, which in turn controls the
fuel pump.
Condition
Fuel pump operation
Ignition switch is turned to ON.
Operates for 1 second
Engine running and cranking
Operates
When engine is stopped (Signal is not sent from camshaft position sensor.)
Stops in 1 second
Except as shown above
Stops
SEF476P
Component Description
NMEC0778
A turbine type design fuel pump is used in the fuel tank.
CONSULT-II Reference Value in Data Monitor
Mode
NMEC0779
MONITOR ITEM
CONDITION
SPECIFICATION
FUEL PUMP RLY
I
Ignition switch is turned to ON (Operates for 1 second)
I
Engine running and cranking
I
When engine is stopped (stops in 1 second)
ON
I
Except as shown above
OFF
GI
MA
EM
LC
FE
CL
MT
AT
PD
AX
SU
BR
ST
RS
BT
HA
SC
EL
IDX
FUEL PUMP
System Description
EC-203