Page 1199 of 2898

DescriptionNJEC1248SYSTEM DESCRIPTIONNJEC1248S01
Sensor Input Signal to ECMECM func-
tionActuator
Throttle position sensor Throttle position
Swirl con-
trol valve
system
controlSwirl control valve control sole-
noid valve via swirl control
valve Ignition switch Start signal
Crankshaft position sensor (POS) Engine speed
Camshaft position sensor (PHASE) Engine speed and cylinder number
Mass air flow sensor Amount of intake air
Engine coolant temperature sensor Engine coolant temperature
This system has a swirl control valve in the intake passage of each cylinder.
While idling and during low engine speed operation, the swirl control valve closes. Thus the velocity of the air
in the intake passage increases, promoting the vaporization of the fuel and producing a swirl in the combus-
tion chamber.
Because of this operation, this system tends to increase the burning speed of the gas mixture, improve fuel
consumption, and increase the stability in running conditions.
Also, except when idling and during low engine speed operation, this system opens the swirl control valve.
The solenoid valve controls swirl control valve's shut/open condition. This solenoid valve is operated by the
ECM.
OPERATIONNJEC1248S02
Engine coolant tempera-
tureThrottle position sensor
(Idle position)Engine speedSwirl control valve con-
trol solenoid valveSwirl control valve
15 - 40ÉC
(59 - 104ÉF)ON Ð
ON Closed
OFF Below 2,400 rpm*
Except above OFF Open
*: The value may vary according to accelerator pedal operation.
SEF081X
CONSULT-II Reference Value in Data Monitor
Mode
NJEC1249Specification data are reference values.
MONITOR ITEM CONDITION SPECIFICATION
SWRL CONT S/V+Engine speed: IdleEngine coolant temperature is
between 15ÉC (59ÉF) to 40ÉC
(104ÉF).ON
Engine coolant temperature is
above 40ÉC (104ÉF).OFF
SWIRL CONTROL VALVE CONTROL SYSTEM (WHERE FITTED)QG
Description
EC-475
Page 1205 of 2898

5 CHECK POWER SUPPLY
1. Disconnect swirl control valve control solenoid valve harness connector.
2. Turn ignition switch ªONº.
3. Check voltage between terminal 2 and ground with CONSULT-II or tester.
SEF619X
OK or NG
OK©GO TO 7.
NG©GO TO 6.
6 DETECT MALFUNCTIONING PART
Check the following.
+Harness connectors E74, F35
+10A fuse
+Harness for open or short between swirl control valve control solenoid valve and fuse
©Repair harness or connectors.
7 CHECK OUTPUT SIGNAL CIRCUIT
1. Turn ignition switch ªOFFº.
2. Disconnect ECM harness connector.
3. Check harness continuity between ECM terminal 104 and swirl control valve control solenoid valve harness connector
terminal 2 with CONSULT-II or tester.
Refer to wiring diagram.
Continuity should exist.
If OK, check harness for short to ground and short to power.
OK or NG
OK©GO TO 8.
NG©Repair open circuit, short to ground or short to power in harness connectors.
8 CHECK SWIRL CONTROL VALVE CONTROL SOLENOID VALVE
Refer to ªComponent Inspectionº, EC-482.
OK or NG
OK©GO TO 10.
NG©Replace swirl control valve control solenoid valve.
9 CHECK ACTUATOR
Refer to ªComponent Inspectionº, EC-482.
OK or NG
OK©INSPECTION END
NG©Replace swirl control valve and actuator.
SWIRL CONTROL VALVE CONTROL SYSTEM (WHERE FITTED)QG
Diagnostic Procedure (Cont'd)
EC-481
Page 1207 of 2898

SEF105X
SWIRL CONTROL VALVE CONTROL SOLENOID VALVENJEC1256S02Check solenoid valve air passage continuity.
With CONSULT-II
Turn ignition switch ªONº and perform ªSWIRL CONT SOL/Vº in
ªACTIVE TESTº mode.
Condition
SWIRL CONT SOL/VAir passage continuity
between A and BAir passage continuity
between A and C
ON Yes No
OFF No Yes
If NG or operation takes more than 1 second, replace solenoid
valve.
Without CONSULT-II
ConditionAir passage continuity
between A and BAir passage continuity
between A and C
12V direct current supply
between terminals 1 and
2Ye s N o
No supply No Yes
If NG or operation takes more than 1 second, replace solenoid
valve.
SEF106X
ONE-WAY VALVENJEC1256S03Check one-way valve air passage continuity.
Condition Air passage continuity
Blow air from side B to A Yes
Blow air from side A to B No
If NG, replace one-way valve.
SEF405S
VACUUM TANKNJEC1256S04Check vacuum tank leakage.
Apply vacuum þ80.0 kPa (þ800 mbar, þ600 mmHg, þ23.62 inHg,
þ11.60 psi). Then keep it for 10 seconds and check there is no
leakage.
If NG, replace vacuum tank.
SWIRL CONTROL VALVE CONTROL SYSTEM (WHERE FITTED)QG
Component Inspection (Cont'd)
EC-483
Page 1215 of 2898

DescriptionNJEC1746SYSTEM DESCRIPTIONNJEC1746S01
Sensor Input Signal to ECMECM func-
tionActuator
Crankshaft position sensor (POS) Engine speed
EGR vol-
ume controlEGR volume control 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
Ignition switch Start signal
Throttle position sensor Throttle position
Vehicle speed sensor Vehicle speed
Battery Battery voltage
Air conditioner switch Air conditioner operation
Power steering oil pressure switch Power steering load signal
Electrical load Electrical load signal
PNP switch Park/Neutral position signal
This system controls flow rate of EGR led from exhaust manifold
to intake manifold. The opening of the EGR by-pass passage in the
EGR volume control valve changes to control the flow rate. A
built-in step motor moves the valve in steps corresponding to the
ECM output pulses. The opening of the valve varies for optimum
engine control. The optimum value stored in the ECM is determined
by considering various engine conditions. The EGR volume control
valve remains close under the following conditions.
+Low engine coolant temperature
+Engine starting
+High-speed engine operation
+Extremely light load engine operation
+Engine idling
+Excessively high engine coolant temperature
+Wide open throttle
+Mass air flow sensor malfunction
+Low battery voltage
SEF551W
EGR VOLUME CONTROL SYSTEM (WHERE FITTED)QG
Description
EC-491
Page 1220 of 2898
Diagnostic ProcedureNJEC1750
1 INSPECTION START
Do you have CONSULT-II?
YesorNo
Ye s©GO TO 2.
No©GO TO 4.
2 CHECK OVERALL FUNCTION-I
With CONSULT-II
1. Turn ignition switch ªONº.
2. Select ªDATA MONITORº mode with CONSULT-II.
3. Confirm that ªCOOLAN TEMP/Sº indicates less than 40ÉC (104ÉF).
If the indication is out of range, cool the engine down.
SEF013Y
4. Start engine and let it idle.
5. Make sure that ªEGR TEMP SENº in ªDATA MONITORº mode indicates more than 3V. Print out the screen or note the
indication.
SEF014Y
OK or NG
OK©GO TO 3.
NG©GO TO 6.
EGR VOLUME CONTROL SYSTEM (WHERE FITTED)QG
Diagnostic Procedure
EC-496
Page 1221 of 2898
3 CHECK OVERALL FUNCTION-II
With CONSULT-II
1. Warm up engine to normal operating temperature.
2. Select ªEGR VOL CONT/Vº in ªACTIVE TESTº mode with CONSULT-II.
3. Keep engine speed at 2,000 rpm and set the ªEGR VOL CONT/Vº opening to ª20 stepº.
4. Make sure the ªEGR TEMP SENº indicated is lower than the value indicated in test No. 2 by 1.0V or more.
SEF015Y
OK or NG
OK©INSPECTION END
NG©GO TO 6.
4 CHECK OVERALL FUNCTION-I
Without CONSULT-II
1. Turn ignition switch ªONº.
2. Confirm that the voltage between ECM terminal 70 (Engine coolant temperature sensor signal) and ground is more
than 2.72V.
If the voltage is out of range, cool the engine down.
SEF016Y
3. Start engine and let it idle.
4. Make sure that the voltage between ECM terminal 72 (EGR temperature sensor signal) and ground is more than 3V.
SEF755Z
OK or NG
OK©GO TO 5.
NG©GO TO 6.
EGR VOLUME CONTROL SYSTEM (WHERE FITTED)QG
Diagnostic Procedure (Cont'd)
EC-497
Page 1222 of 2898
5 CHECK OVERALL FUNCTION-II
Without CONSULT-II
1. Warm up engine to normal operating temperature.
2. Rev engine from idle up to about 3,000 rpm two to three times.
3. Make sure the voltage between ECM terminal 72 and ground is lower than the voltage measured in test No. 4 by 1.0V
or more.
SEF755Z
OK or NG
OK©INSPECTION END
NG©GO TO 6.
6 CHECK EGR TEMPERATURE SENSOR POWER SUPPLY
1. Turn ignition switch ªOFFº.
2. Disconnect EGR temperature sensor harness connector.
SEF127X
3. Turn ignition switch ªONº.
4. Check voltage between terminal 1 and ground with CONSULT-II or tester.
SEF896X
OK or NG
OK©GO TO 7.
NG©Repair harness or connectors.
EGR VOLUME CONTROL SYSTEM (WHERE FITTED)QG
Diagnostic Procedure (Cont'd)
EC-498
Page 1223 of 2898

7 CHECK EGR TEMPERATURE SENSOR GROUND CIRCUIT
1. Turn ignition switch ªOFFº.
2. Check harness continuity between EGR temperature sensor harness terminal 2 and engine ground.
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 9.
NG©GO TO 8.
8 DETECT MALFUNCTIONING PART
Check the following.
+Harness for open or short between EGR temperature sensor and ECM
+Harness for open or short between TCM (Transmission Control Module) and ECM
+Joint connector-3 (If so equipped)
+Joint connector-6 (If so equipped)
©Repair open circuit or short to ground or short to power in harness or connector.
9 CHECK EGR TEMPERATURE SENSOR
Refer to ªComponent Inspectionº, EC-502.
OK or NG
OK©GO TO 10.
NG©Replace EGR temperature sensor.
10 CHECK EGR VOLUME CONTROL VALVE POWER SUPPLY
1. Disconnect EGR volume control valve harness connector.
2. Turn ignition switch ªONº.
3. Check voltage between terminals 2, 5 and ground with CONSULT-II or tester.
SEF782Z
OK or NG
OK©GO TO 12.
NG©GO TO 11.
11 DETECT MALFUNCTIONING PART
Check the following.
+15A fuse
+Harness connectors E75, F36
+Harness for open or short between fuse and ECM relay
+ECM relay
+Harness for open or short between EGR volume control valve and ECM relay.
©Repair harness or connectors, or replace fuse or ECM relay.
EGR VOLUME CONTROL SYSTEM (WHERE FITTED)QG
Diagnostic Procedure (Cont'd)
EC-499