Page 937 of 3051
Wiring DiagramNLEC0440MODELS WITH ECM IN ENGINE COMPARTMENTNLEC0440S01
YEC675
START SIGNALQG18DE
Wiring Diagram
EC-512
Page 938 of 3051
MODELS WITH ECM IN CABINNLEC0440S02
YEC903
START SIGNALQG18DE
Wiring Diagram (Cont'd)
EC-513
Page 939 of 3051
Diagnostic Procedure=NLEC0443
1 INSPECTION START
Do you have CONSULT-II?
YesorNo
Ye s©GO TO 2.
No©GO TO 3.
2 CHECK OVERALL FUNCTION
With CONSULT-II
1. Turn ignition switch ªONº.
2. Check ªSTART SIGNALº in ªDATA MONITORº mode with CONSULT-II under the following conditions.
SEF227Y
OK or NG
OK©INSPECTION END
NG©GO TO 4.
3 CHECK OVERALL FUNCTION
Without CONSULT-II
1. Turn ignition switch to ªSTARTº.
2. Check voltage between ECM terminal 41 and ground under the following conditions.
SEF613Y
OK or NG
OK©INSPECTION END
NG©GO TO 4.
START SIGNALQG18DE
Diagnostic Procedure
EC-514
Page 940 of 3051
4 DETECT MALFUNCTIONING PART
Check the following.
+Harness connectors M49, F43 (where fitted)
+Harness connectors M71, F45 (where fitted)
+10A fuse
+Harness for open or short between ECM and ignition switch
OK or NG
OK©GO TO 5.
NG©Repair open circuit or short to ground or short to power in harness or connectors.
5 CHECK INTERMITTENT INCIDENT
Perform ªTROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENTº, EC-145.
©INSPECTION END
START SIGNALQG18DE
Diagnostic Procedure (Cont'd)
EC-515
Page 941 of 3051

System DescriptionNLEC0444
Sensor Input Signal to ECMECM func-
tionActuator
Crankshaft position sensor (POS) Engine speed
Fuel pump
controlFuel pump relay Camshaft position sensor (PHASE) Engine speed and cylinder number
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 180É signal from the camshaft position sensor, it knows that the engine is
rotating, and causes the pump to perform. If the 180É 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 crankshaft position sensor
and camshaft position sensor.)Stops in 1.5 seconds
Except as shown aboveStops
SEF605X
Component DescriptionNLEC0501A turbine type design fuel pump is used in the fuel tank.
CONSULT-II Reference Value in Data Monitor
Mode
NLEC0445
MONITOR ITEM CONDITION SPECIFICATION
FUEL PUMP RLY+Ignition switch is turned to ON (Operates for 1 second)
+Engine running and cranking
+When engine is stopped (stops in 1.5 seconds)ON
+Except as shown above OFF
FUEL PUMPQG18DE
System Description
EC-516
Page 942 of 3051
ECM Terminals and Reference Value=NLEC0446Specification data are reference values and are measured between each terminal and ground.
CAUTION:
Do not use ECM ground terminals when measuring input/output voltage. Doing so may result in dam-
age to the ECM's transistor. Use a ground other than ECM terminals, such as the ground.
TERMI-
NAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
21 B/P Fuel pump relay[Ignition switch ªONº]
+For 1 second after turning ignition switch ªONº
[Engine is running]0-1V
[Ignition switch ªONº]
+More than 1 second after turning ignition switch
ªONºBATTERY VOLTAGE
(11 - 14V)
FUEL PUMPQG18DE
ECM Terminals and Reference Value
EC-517
Page 943 of 3051
Wiring DiagramNLEC0447MODELS WITH ECM IN ENGINE COMPARTMENTNLEC0447S01
YEC714
FUEL PUMPQG18DE
Wiring Diagram
EC-518
Page 944 of 3051
MODELS WITH ECM IN CABINNLEC0447S02
YEC904
FUEL PUMPQG18DE
Wiring Diagram (Cont'd)
EC-519