Page 477 of 1033

4 CHECK HEAT UP SWITCH POWER SUPPLY CIRCUIT
1. Turn heat up switch ªOFFº.
2. Turn ignition switch ªOFFº.
3. Disconnect heat up switch harness connector.
4. Turn ignition switch ªONº.
5. Check voltage between heat up switch terminal 6 and ground with CONSULT-II or tester.
SEF304Z
OK or NG
OKcGO TO 6.
NGcGO TO 5.
5 DETECT MALFUNCTIONING PART
Check the following.
+Fuse block (J/B) connector M3
+10A fuse
+Harness for open or short between heat up switch and fuse
cRepair open circuit or short to ground or short to power in harness or connectors.
6 CHECK HEAT UP SWITCH INPUT SIGNAL CIRCUIT FOR OPEN OR SHORT
1. Turn ignition switch ªOFFº.
2. Disconnect ECM harness connector.
3. Check harness continuity between ECM terminal 59 and heat up switch terminal 5. Refer to Wiring Diagram.
Continuity should exist.
4. Also check harness for short to ground and short to power.
OK or NG
OKcGO TO 8.
NGcGO TO 7.
7 DETECT MALFUNCTIONING PART
Check the following.
+Harness connectors M51, F6
+Harness for open or short between heat up switch and ECM
cRepair open circuit or short to ground or short to power in harness or connectors.
HEAT UP SWITCHZD30DDTi
Diagnostic Procedure (Cont'd)
EC-1244
Page 479 of 1033

Description
SYSTEM DESCRIPTION
Sensor Input Signal to ECMECM
FunctionActuator
Ignition switch Start signal
Swirl
control
valve
controlSwirl control valve control solenoid valve
¯Vacuum signal
Swirl control valve actuator
¯Swirl control valve Crankshaft position sensor (TDC) Engine speed
PNP switch Park/Neutral position signal
Engine coolant temperature sensor Engine coolant temperature
This system has a swirl control valve in the throttle body.
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 combustion 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. In this condition, this
system tends to increase power by improving intake efficiency
via reduction of intake flow resistance, intake flow.
The solenoid valve controls swirl control valve's shut/open con-
dition. This solenoid valve is operated by the ECM.
PNP switch Engine speedEngine cool-
ant tempera-
tureSwirl control
valve control
solenoid valveSwirl control
valve
OFFLess than
1,250 rpmLess than
50ÉC (122ÉF)OFF Open
More than
50ÉC (122ÉF)ON Closed
More than
1,250 rpmLess than
50ÉC (122ÉF)OFF Open
More than
50ÉC (122ÉF)OFF Open
ON Ð Ð OFF Open
SEF452Z
SWIRL CONTROL VALVE CONTROL
SOLENOID VALVEZD30DDTi
EC-1246
Page 480 of 1033

COMPONENT DESCRIPTION
Swirl control valve control solenoid valve
The swirl control valve control solenoid valve responds to signals
from the ECM. When the ECM sends an ON (ground) signal, the
solenoid valve is bypassed to apply vacuum pump vacuum to the
swirl control valve actuator. This operation closes the swirl con-
trol valve. When the ECM sends an OFF signal, the vacuum
signal is cut and the swirl control valve opens.
CONSULT-II Reference Value in Data Monitor
Mode
Specification data are reference values.
MONITOR ITEM CONDITION SPECIFICATION
SWRL CONT S/V+Lift up the vehicle
+Engine: After warming up, let it
idle for more than 1 second.
+Air conditioner switch: OFF
+No-loadShift lever: Except ªPº and ªNeutralº
positionON
Shift lever: ªNeutralº position OFF
ECM Terminals and Reference Value
Specification 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 damage the
ECM's transistor. Use a ground other than ECM terminals, such as the ground.
TER-
MINAL
NO.WIRE
COLORITEM CONDITIONDATA
(DC Voltage and Pulse
Signal)
54 L/BSwirl control valve control
solenoid valveEngine is running.
Warm-up condition
At idle speed for more than 1 second.
Lift up the vehicle
Gear position is except ªPº and ªNeutralºApproximately 0.1V
Engine is running.
Idle speed
Lift up the vehicle
Gear position is ªPº or ªNeutralºBATTERY VOLTAGE
(11 - 14V)
SEF284Z
SWIRL CONTROL VALVE CONTROL
SOLENOID VALVEZD30DDTi
Description (Cont'd)
EC-1247
Page 485 of 1033

8 CHECK SWIRL CONTROL VALVE CONTROL SOLENOID VALVE POWER SUPPLY CIRCUIT
1. Turn ignition switch ªOFFº.
2. Disconnect swirl control valve control solenoid valve harness connector.
SEF284Z
3. Turn ignition switch ªONº.
4. Check voltage between swirl control valve control solenoid valve terminal 2 and ground with CONSULT-II or tester.
SEF312Z
OK or NG
OKcGO TO 10.
NGcGO TO 9.
9 DETECT MALFUNCTIONING PART
Check the following.
+Harness connectors M52, F7
+Fuse block (J/B) connector M2
+10A fuse
+Harness for open or short between swirl control valve control solenoid valve and fuse
cRepair open circuit or short to ground or short to power in harness or connectors.
10 CHECK SWIRL CONTROL VALVE CONTROL SOLENOID VALVE OUTPUT SIGNAL CIRCUIT FOR OPEN OR SHORT
1. Turn ignition switch ªOFFº.
2. Disconnect ECM harness connector.
3. Check harness continuity between ECM terminal 54 and swirl control valve control solenoid valve terminal 1. Refer to Wiring
Diagram.
Continuity should exist.
4. Also check harness for short to ground and short to power.
OK or NG
OKcGO TO 11.
NGcRepair open circuit or short to ground or short to power in harness or connectors.
SWIRL CONTROL VALVE CONTROL
SOLENOID VALVEZD30DDTi
Diagnostic Procedure (Cont'd)
EC-1252
Page 487 of 1033

Description
Vibration when stopping the engine can be controlled by cutting
intake air right before the fuel is cut. The intake air control valve
control solenoid valve controls the ON-OFF load of the intake air
control valve actuator. As a result, the intake air control valve
control solenoid valve will be turned ON when the ignition switch
is turned OFF with the engine running and when the engine
stalls. After the engine has stopped, the intake air control valve
control solenoid valve will return to fully open.
ECM Terminals and Reference Value
Specification 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 damage the
ECM's transistor. Use a ground other than ECM terminals, such as the ground.
TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
2 R/WIntake air control valve
control solenoid valveEngine is running.
BATTERY VOLTAGE
(11 - 14V)
Ignition switch ªOFFº
For a few seconds after engine stopsApproximately 0.1V
SEF284Z
INTAKE AIR CONTROL VALVE CONTROL
SOLENOID VALVEZD30DDTi
EC-1254
Page 492 of 1033

6 CHECK INTAKE AIR CONTROL VALVE CONTROL SOLENOID VALVE POWER SUPPLY CIRCUIT-II
1. Turn ignition switch ªOFFº.
2. Disconnect ECM relay.
SEF225Z
3. Check harness continuity between intake air control valve control solenoid valve terminal 2 and ECM relay terminal 7. Refer to
Wiring Diagram.
Continuity should exist.
4. Also check harness for short to ground and short to power.
OK or NG
OKcGO TO 8.
NGcGO TO 7.
7 DETECT MALFUNCTIONING PART
Check the following.
+Harness connectors M50, F5
+Harness for open or short between intake air control valve control solenoid valve and ECM relay
cRepair open circuit or short to ground or short to power in harness or connectors.
8 CHECK INTAKE AIR CONTROL VALVE CONTROL SOLENOID VALVE POWER SUPPLY CIRCUIT-III
Check voltage between ECM relay terminal 6 and ground with CONSULT-II or tester.
SEF297Z
OK or NG
OKcGO TO 10.
NGcGO TO 9.
9 DETECT MALFUNCTIONING PART
Check the following.
+Harness connectors M21, E127
+10A fuse
+Harness for open or short between ECM relay and battery
cRepair open circuit or short to ground or short to power in harness or connectors.
INTAKE AIR CONTROL VALVE CONTROL
SOLENOID VALVEZD30DDTi
Diagnostic Procedure (Cont'd)
EC-1259
Page 493 of 1033

10 CHECK ECM RELAY
1. Apply 12V direct current between ECM relay terminals 1 and 2.
2. Check continuity between ECM relay terminals 3 and 5, 6 and 7.
SEF296X
OK or NG
OKcGO TO 13.
NGcReplace ECM relay.
11 CHECK INTAKE AIR CONTROL VALVE CONTROL SOLENOID VALVE OUTPUT SIGNAL CIRCUIT FOR OPEN OR
SHORT
1. Turn ignition switch ªOFFº.
2. Disconnect ECM harness connector.
3. Check harness continuity between ECM terminal 2 and intake air control valve control solenoid valve terminal 1. Refer to Wiring
Diagram.
Continuity should exist.
4. Also check harness for short to ground and short to power.
OK or NG
OKcGO TO 12.
NGcRepair open circuit or short to ground or short to power in harness or connectors.
12 CHECK INTAKE AIR CONTROL VALVE CONTROL SOLENOID VALVE
1. Apply 12V direct current between intake air control valve control solenoid valve terminals.
2. Check air passage continuity of intake air control valve control solenoid valve under the following conditions.
SEF335X
OK or NG
OKcGO TO 13.
NGcReplace intake control valve control solenoid valve.
13 CHECK INTERMITTENT INCIDENT
Perform ªTROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENTº, EC-1076.
cINSPECTION END
INTAKE AIR CONTROL VALVE CONTROL
SOLENOID VALVEZD30DDTi
Diagnostic Procedure (Cont'd)
EC-1260
Page 494 of 1033
Description
The load from the variable nozzle turbocharger control solenoid
valve controls the actuator. By changing the variable nozzle vane
opening through the rods, the intake air volume is adjusted.
The variable nozzle turbocharger control solenoid valve is moved
by ON/OFF pulse from the ECM. The longer the ON pulse, the
charge air pressure rises.
CONSULT-II Reference Value in Data Monitor
Mode
Specification data are reference values.
MONITOR ITEM CONDITION SPECIFICATION
VNT S/V 1+Engine: After warming up
+Air conditioner switch: ªOFFº
+Shift lever: Neutral position
+No-loadIdle Approx. 56%
2,000 rpm Approx. 20%
SEF453Z
SEF287Z
VARIABLE NOZZLE TURBOCHARGER CONTROL
SOLENOID VALVEZD30DDTi
EC-1261