2001 NISSAN ALMERA Ignition system

12 CHECK OUTPUT SIGNAL CIRCUIT
1. Turn ignition switch ªOFFº.
2. Disconnect ECM harness connector.
3. Check harness continuity between
ECM terminal 8 and EGR volume control valve terminal 1,
ECM terminal 9 and EGR volume control valve terminal 4,
ECM terminal 17 and EGR volume control valve terminal 3,
ECM terminal 18 and EGR volume control valve terminal 6.
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 13.
NG©Repair open circuit, short to ground or short to power in harness connectors.
13 CHECK EGR PASSAGE
Check EGR passage for clogging and cracks.
OK or NG
OK©GO TO 14.
NG©Repair or replace EGR passage.
14 CHECK EGR VOLUME CONTROL VALVE
Refer to ªCOMPONENT INSPECTIONº, EC-501.
OK or NG
OK©GO TO 15.
NG©Replace EGR volume control valve.
15 CHECK INTERMITTENT INCIDENT
Perform ªTROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENTº, EC-177.
©INSPECTION END
EGR VOLUME CONTROL SYSTEM (WHERE FITTED)QG
Diagnostic Procedure (Cont'd)
EC-500

SEF069X
SEF605Y
SEF015Y
SEF560W
Component InspectionNJEC1751EGR VOLUME CONTROL VALVENJEC1751S01With CONSULT-II
1) Disconnect EGR volume control valve harness connector.
2) Check resistance between the following terminals.
terminal 2 and terminals 1, 3
terminal 5 and terminals 4, 6
Temperature ÉC (ÉF) ResistanceW
20 (68) 20 - 24
3) Reconnect EGR volume control valve harness connector.
4) Remove EGR volume control valve from cylinder head.
(The EGR volume control valve harness connector should
remain connected.)
5) Turn ignition switch ªONº.
6) Perform ªEGR VOL CONT/Vº in ªACTIVE TESTº mode with
CONSULT-II. Check that EGR volume control valve shaft
moves smoothly forward and backward according to the valve
opening.
If NG, replace the EGR volume control valve.
Without CONSULT-II
1) Disconnect EGR volume control valve harness connector.
2) Check resistance between the following terminals.
terminal 2 and terminals 1, 3
terminal 5 and terminals 4, 6
Temperature ÉC (ÉF) ResistanceW
20 (68) 20 - 24
3) Turn ignition switch ªONº and ªOFFº. Check that EGR volume
control valve shaft moves smoothly forward and backward
according to the ignition switch position.
If NG, replace the EGR volume control valve.
EGR VOLUME CONTROL SYSTEM (WHERE FITTED)QG
Diagnostic Procedure (Cont'd)
EC-501

DescriptionNJEC1752SYSTEM DESCRIPTIONNJEC1752S01
Sensor Input Signal to ECMECM func-
tionActuator
Crankshaft position sensor (POS) Engine speed
EVAP can-
ister purge
controlEVAP canister purge volume
control solenoid valve Camshaft position sensor (PHASE) Engine speed and cylinder number
Mass air flow sensor Amount of intake air
Engine coolant temperature sensor Engine coolant temperature
Battery Battery voltage
Ignition switch Start signal
Closed throttle position switch (If so
equipped)Closed throttle position
Throttle position sensor Throttle position
Heated oxygen sensor 1 (front)Density of oxygen in exhaust gas
(Mixture ratio feedback signal)
Vehicle speed sensor Vehicle speed
This system controls flow rate of fuel vapor from the EVAP canis-
ter. The opening of the vapor by-pass passage in the EVAP canis-
ter purge volume control solenoid valve changes to control the flow
rate. The EVAP canister purge volume control solenoid valve
repeats ON/OFF operation according to the signal sent from the
ECM. The opening of the valve varies for optimum engine control.
The optimum value stored in the ECM is determined by consider-
ing various engine conditions. When the engine is operating, the
flow rate of fuel vapor from the EVAP canister is regulated as the
air flow changes.
SEF337U
COMPONENT DESCRIPTIONNJEC1752S02The EVAP canister purge volume control solenoid valve uses a
ON/OFF duty to control the flow rate of fuel vapor from the EVAP
canister. The EVAP canister purge volume control solenoid valve
is moved by ON/OFF pulses from the ECM. The longer the ON
pulse, the greater the amount of fuel vapor that will flow through the
valve.
CONSULT-II Reference Value in Data Monitor
Mode
NJEC1753
MONITOR ITEM CONDITION SPECIFICATION
PURG VOL C/V+Engine: After warming up
+No-loadIdle 0%
Revving engine Ð
EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVEQG
Description
EC-503

DescriptionNJEC1758SYSTEM DESCRIPTIONNJEC1758S01
Sensor Input Signal to ECMECM func-
tionActuator
Crankshaft position sensor (POS) Engine speed
Idle air
controlIACV-AAC valve Camshaft position sensor (PHASE) Engine speed and cylinder number
Engine coolant temperature sensor Engine coolant temperature
Ignition switch Start signal
Throttle position sensor Throttle position
PNP switch Park/Neutral position
Air conditioner switch Air conditioner operation
Power steering oil pressure switch Power steering load signal
Battery Battery voltage
Vehicle speed sensor Vehicle speed
Cooling fan Cooling fan operation
Electrical load Electrical load signal
This system automatically controls engine idle speed to a specified
level. Idle speed is controlled through fine adjustment of the
amount of air which by-passes the throttle valve via IACV-AAC
valve. The IACV-AAC valve changes the opening of the air by-pass
passage to control the amount of auxiliary air. This valve is actu-
ated by a step motor built into the valve, which moves the valve in
the axial direction in steps corresponding to the ECM output sig-
nals. One step of IACV-AAC valve movement causes the respec-
tive opening of the air by-pass passage. (i.e. when the step
advances, the opening is enlarged.) The opening of the valve is
varied to allow for optimum control of the engine idling speed. The
crankshaft position sensor (POS) detects the actual engine speed
and sends a signal to the ECM. The ECM then controls the step
position of the IACV-AAC valve so that engine speed coincides with
the target value memorized in ECM. The target engine speed is the
lowest speed at which the engine can operate steadily. The opti-
mum value stored in the ECM is determined by taking into consid-
eration various engine conditions, such as during warm up,
deceleration, and engine load (air conditioner, power steering, cool-
ing fan operation and electrical load).
SEF937W
COMPONENT DESCRIPTIONNJEC1758S02IACV-AAC ValveNJEC1758S0201The IACV-AAC valve is operated by a step motor for centralized
control of auxiliary air supply. This motor has four winding phases
and is actuated by the output signals of ECM which turns ON and
OFF two windings each in sequence. Each time the IACV-AAC
valve opens or closes to change the auxiliary air quantity, the ECM
sends a pulse signal to the step motor. When no change in the
auxiliary air quantity is needed, the ECM does not issue the pulse
signal. A certain voltage signal is issued so that the valve remains
at that particular opening.
IDLE AIR CONTROL VALVE (IACV) Ð AUXILIARY AIR CONTROL
(AAC) VALVE
QG
Description
EC-511

8 CHECK VACUUM HOSES AND TUBES
1. Disconnect vacuum hoses between the air control valve (Power steering) and vacuum port, air control valve (Power
steering) and air duct.
2. Check hoses and tubes for cracks, clogging, improper connection or disconnection.
SEF109L
OK or NG
OK©GO TO 9.
NG©Repair hoses or tubes.
9 CHECK IACV-AAC VALVE
Refer to ªComponent Inspectionº, EC-519.
OK or NG
OK©GO TO 11.
NG©GO TO 10.
10 REPLACE IACV-AAC VALVE
1. Replace IACV-AAC valve assembly.
2. Perform ªIdle Air Volume Learningº, EC-57.
Is the result CMPLT or INCMP?
CMPLT or INCMP
CMPLT©INSPECTION END
INCMP©Follow the construction of ªIdle Air Volume Learningº.
11 CHECK TARGET IDLE SPEED
1. Turn ignition switch ªOFFº.
2. Reconnect all harness connectors and vacuum hose.
3. Start engine and warm it up to normal operating temperature.
4. Also warm up transmission to normal operating temperature.
+For A/T models with CONSULT-II, drive vehicle until ªFLUID TEMP SEº in ªDATA MONITORº mode of ªA/Tº system indi-
cates less than 0.9V.
+For A/T models without CONSULT-II and M/T models, drive vehicle for 10 minutes.
5. Stop vehicle with engine running.
6. Check target idle speed.
M/T: 700±50 rpm
A/T: 800±50 rpm (in ªPº or ªNº position)
OK or NG
OK©GO TO 12.
NG©Perform ªIdle Air Volume Learningº, EC-57.
IDLE AIR CONTROL VALVE (IACV) Ð AUXILIARY AIR CONTROL
(AAC) VALVE
QG
Diagnostic Procedure (Cont'd)
EC-518

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

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

System ChartNJEC0611
Input (Sensor) ECM Function Output (Actuator)
+Electronic control fuel injection pump
+Crankshaft position sensor (TDC)
+Engine coolant temperature sensor
+Accelerator position sensor
+Accelerator position switch
+Park/Neutral position (PNP) switch*
+Ignition switch
+Battery voltage
+Vehicle speed sensor
+Air conditioner switch
+Mass air flow sensor
+Stop lamp switchFuel injection controlElectronic control fuel injection
pump
Fuel injection timing controlElectronic control fuel injection
pump
Fuel cut controlElectronic control fuel injection
pump
Glow control system Glow relay & glow lamp
On board diagnostic system MI (On the instrument panel)
EGR volume control EGR volume control valve
Cooling fan control Cooling fan relay
Air conditioning cut control Air conditioner relay
*: If so equipped
ENGINE AND EMISSION CONTROL OVERALL SYSTEMYD
System Chart
EC-609