Page 1284 of 2898
4 DETECT MALFUNCTIONING PART
Check the following.
+Harness connectors M63, F102
+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-177.
©INSPECTION END
START SIGNALQG
Diagnostic Procedure (Cont'd)
EC-560
Page 1285 of 2898

System DescriptionNJEC0444
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 DescriptionNJEC0501A turbine type design fuel pump is used in the fuel tank.
CONSULT-II Reference Value in Data Monitor
Mode
NJEC0445
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 PUMPQG
System Description
EC-561
Page 1286 of 2898
ECM Terminals and Reference Value=NJEC0446Specification 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 PUMPQG
ECM Terminals and Reference Value
EC-562
Page 1288 of 2898
Diagnostic ProcedureNJEC0448
1 CHECK OVERALL FUNCTION
1. Turn ignition switch ªONº.
2. Pinch fuel feed hose with fingers.
JEF133Y
Fuel pressure pulsation should be felt on the fuel feed hose for 1 second after ignition switch is turned ªONº.
OK or NG
OK©INSPECTION END
NG©GO TO 2.
2 CHECK POWER SUPPLY
1. Turn ignition switch ªOFFº.
2. Disconnect fuel pump relay.
JEF134Y
3. Turn ignition switch ªONº.
4. Check voltage between terminals 1, 5 and ground with CONSULT-II or tester.
SEF607X
OK or NG
OK©GO TO 4.
NG©GO TO 3.
FUEL PUMPQG
Diagnostic Procedure
EC-564
Page 1289 of 2898

3 DETECT MALFUNCTIONING PART
Check the following.
+10A fuse
+15A fuse
+Harness for open or short between fuse and fuel pump relay
©Repair harness or connectors.
4 CHECK POWER GROUND CIRCUIT
1. Turn ignition switch ªOFFº.
2. Disconnect fuel level sensor unit and fuel pump harness connector.
JEF135Y
3. Check harness continuity between fuel level sensor unit and fuel pump harness connector terminal 3 and body ground,
terminal 5 and fuel pump relay connector terminal 3.
Refer to wiring diagram.
Continuity should exist.
4. Also check harness for short to ground and short to power.
OK or NG
OK©GO TO 6.
NG©GO TO 5.
5 DETECT MALFUNCTIONING PART
Check the following.
+Harness for open or short between fuel pump and body ground
+Harness for open or short between fuel pump and fuel pump relay
©Repair open circuit or short to ground or short to power in harness or connectors.
6 CHECK OUTPUT SIGNAL CIRCUIT
1. Disconnect ECM harness connector.
2. Check harness continuity between ECM terminal 21 and fuel pump relay connector terminal 2.
Refer to wiring diagram.
Continuity should exist.
3. Also check harness for short to ground and short to power.
OK or NG
OK©GO TO 8.
NG©GO TO 7.
7 DETECT MALFUNCTIONING PART
Check the following.
+Harness connectors B38, M81
+Harness connectors M63, F102
+Harness for open or short between ECM and fuel pump relay
NG©Repair open circuit or short to ground or short to power in harness or connectors.
FUEL PUMPQG
Diagnostic Procedure (Cont'd)
EC-565
Page 1294 of 2898

4 CHECK GROUND CIRCUIT
1. Turn ignition switch ªOFFº.
2. Disconnect power steering oil pressure switch harness connector.
3. Check harness continuity between power steering oil pressure switch harness terminal 2 and engine ground.
Refer to wiring diagram.
Continuity should exist.
4. Also check harness for short to ground and short to power.
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 INPUT SIGNAL CIRCUIT
1. Disconnect ECM harness connector.
2. Check harness continuity between ECM terminal 46 and power steering oil pressure switch harness terminal 1.
Refer to wiring diagram.
Continuity should exist.
3. Also check harness for short to ground and short to power.
OK or NG
OK©GO TO 7.
NG©GO TO 6.
6 DETECT MALFUNCTIONING PART
Check the harness for open or short between ECM and power steering oil pressure switch.
©Repair open circuit or short to ground or short to power in harness or connectors.
7 CHECK POWER STEERING OIL PRESSURE SWITCH
Refer to ªComponent Inspectionº, EC-570.
OK or NG
OK©GO TO 8.
NG©Replace power steering oil pressure switch.
8 CHECK INTERMITTENT INCIDENT
Perform ªTROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENTº, EC-177.
©INSPECTION END
Component InspectionNJEC0455POWER STEERING OIL PRESSURE SWITCHNJEC0455S011. Disconnect power steering oil pressure switch harness con-
nector then start engine.
2. Check continuity between terminals 1 and 2.
Refer to wiring diagram.
Conditions Continuity
Steering wheel is being fully turned. Yes
Steering wheel is not being turned. No
POWER STEERING OIL PRESSURE SWITCHQG
Diagnostic Procedure (Cont'd)
EC-570
Page 1296 of 2898

JEF147Y
DescriptionNJEC0580The refrigerant pressure sensor is installed at the liquid tank of the
air conditioner system. The sensor uses an electrostatic volume
pressure transducer to convert refrigerant pressure to voltage. The
voltage signal is sent to ECM, and ECM controls cooling fan sys-
tem.
SEF099X
ECM Terminals and Reference ValueNJEC0581Specification 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)
58 B Sensor's ground[Engine is running]
+Warm-up condition
+Idle speedApproximately 0V
74 R/LRefrigerant pressure
sensor[Engine is running]
+Warm-up condition
+Both A/C switch and blower switch are ªONº
(Compressor operates.)1.0 - 4.0V
111 R Sensor's power supply[Ignition switch ªONº]Approximately 5V
REFRIGERANT PRESSURE SENSORQG
Description
EC-572
Page 1299 of 2898
Diagnostic ProcedureNJEC0590
1 CHECK REFRIGERANT PRESSURE SENSOR OVERALL FUNCTION
1. Start engine and warm it up to normal operating temperature.
2. Turn A/C switch and blower switch ªONº.
3. Check voltage between ECM terminal 74 and ground with CONSULT-II or tester.
SEF952XA
OK or NG
OK©INSPECTION END
NG©GO TO 2.
2 CHECK REFRIGERANT PRESSURE SENSOR POWER SUPPLY CIRCUIT
1. Turn A/C switch and blower switch ªOFFº.
2. Stop engine.
3. Disconnect refrigerant pressure sensor harness connector.
JEF147Y
4. Turn ignition switch ªONº.
5. Check voltage between refrigerant pressure sensor terminal 3 and ground with CONSULT-II or tester.
SEF953X
OK or NG
OK©GO TO 4.
NG©GO TO 3.
REFRIGERANT PRESSURE SENSORQG
Diagnostic Procedure
EC-575