2001 INFINITI QX4 IDX

10 CHECK CRANKSHAFT POSITION SENSOR (REF)-II
Check resistance between CKPS (REF) terminals 1 and 2.
SEF350X
OK or NG
OK (With CONSULT-II)©GO TO 11.
OK (Without CONSULT-
II)©GO TO 12.
NG©Replace crankshaft position sensor (REF).
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DTC P1130 SWIRL CONTROL VALVE CONTROL SOLENOID VALVE
Diagnostic Procedure (Cont'd)
EC-479

12 CHECK THROTTLE POSITION SENSOR
Without CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Stop engine (ignition switch OFF).
3. Remove the vacuum hose connected to the throttle opener.
4. Connect suitable vacuum hose to the vacuum pump and the opener.
5. Apply vacuum [more than þ40.0 kPa (þ300 mmHg, þ11.81 inHg)] until the throttle drum becomes free from the rod of
the throttle opener.
SEF793W
6. Turn ignition switch ON.
7. Check voltage between ECM terminal 91 (Throttle position sensor signal) and ground.
Voltage measurement must be made with throttle position sensor installed in vehicle.
MTBL0231
OK or NG
OK©GO TO 14.
NG©GO TO 13.
13 ADJUST CLOSED THROTTLE POSITION SWITCH
Adjust closed throttle position switch. Refer to ªBasic Inspectionº, EC-101.
MTBL0655
OK or NG
OK©GO TO 14.
NG©Replace throttle position sensor. To adjust it, perform ªBasic Inspectionº, EC-101.
14 CHECK INTERMITTENT INCIDENT
Perform ªTROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENTº, EC-140.
©INSPECTION END
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DTC P1130 SWIRL CONTROL VALVE CONTROL SOLENOID VALVE
Diagnostic Procedure (Cont'd)
EC-481

TERMI-
NAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
89 ORIntake valve timing
control position sen-
sors (LH)[Engine is running]
IWarm-up condition
IIdle speedApproximately 0.5V
SEF351Z
[Engine is running]
IWarm-up condition
IEngine speed is 2,000 rpm.Approximately 0.5V
SEF352Z
On Board Diagnosis LogicNBEC0708Malfunction is detected when an excessively high or low voltage
from the sensor is sent to ECM.
Possible CauseNBEC0709IHarness or connectors
(Intake valve timing control position sensor circuit is open or
shorted)
IIntake valve timing control position sensor.
ICrankshaft position sensor (REF)
ICrankshaft position sensor (POS)
ICamshaft position sensor (PHASE)
SEF353Z
DTC Confirmation ProcedureNBEC0710NOTE:
If ªDTC Confirmation Procedureº has been previously
conducted, always turn ignition switch ªOFFº and wait at least
10 seconds before conducting the next test.
WITH CONSULT-IINBEC0710S011) Turn ignition switch ªONº.
2) Select ªDATA MONITORº mode with CONSULT-II.
3) Maintain the following conditions for at least 10 seconds.
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DTC P1140 (RIGHT, -B1), P1145 (LEFT, -B2) INTAKE VALVE TIMING CONTROL
POSITION SENSOR (CIRCUIT)
ECM Terminals and Reference Value (Cont'd)
EC-483

Wiring DiagramNBEC0711RIGHT BANKNBEC0711S01
MEC987C
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DTC P1140 (RIGHT, -B1), P1145 (LEFT, -B2) INTAKE VALVE TIMING CONTROL
POSITION SENSOR (CIRCUIT)
Wiring Diagram
EC-485

Diagnostic ProcedureNBEC0712
1 RETIGHTEN GROUND SCREWS
1. Turn ignition switch ªOFFº.
2. Loosen and retighten engine ground screws.
SEF959Y
©GO TO 2.
2 CHECK INTAKE VALVE TIMING CONTROL POSITION SENSOR POWER SUPPLY CIRCUIT
1. Disconnect intake valve timing control position sensor harness connector.
SEF360Z
2. Turn ignition switch ªONº.
3. Check voltage between intake valve timing control position sensor harness connector terminal 3 and ground with CON-
SULT-II or tester.
SEF370X
4. Also check harness for short to ground and short to power.
OK or NG
OK©GO TO 4.
NG©GO TO 3.
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DTC P1140 (RIGHT, -B1), P1145 (LEFT, -B2) INTAKE VALVE TIMING CONTROL
POSITION SENSOR (CIRCUIT)
Diagnostic Procedure
EC-487

7 CHECK IMPROPER INSTALLATION
1. Loosen and retighten the fixing bolt of the intake valve timing control position sensor.
2. Reconnect harness connector disconnected.
3. Perform ªDTC Confirmation Procedureº, EC-483 again.
Is a 1st trip DTC P1140 (RIGHT, -B1), P1145 (LEFT, -B2) detected?
Ye s©GO TO 8.
No©INSPECTION END
8 CHECK INTAKE VALVE TIMING CONTROL POSITION SENSOR
1. Disconnect intake valve timing control position sensor connector.
2. Loosen the fixing bolt of the sensor.
3. Remove the sensor.
4. Visually check the sensor for chipping.
SEF362Z
OK or NG
OK©GO TO 9.
NG©Replace intake valve timing control position sensor.
9 CHECK INTAKE VALVE TIMING CONTROL POSITION SENSOR-II
Check resistance as shown below.
SEF363Z
OK or NG
OK©GO TO 10.
NG©Replace intake valve timing control position sensor.
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DTC P1140 (RIGHT, -B1), P1145 (LEFT, -B2) INTAKE VALVE TIMING CONTROL
POSITION SENSOR (CIRCUIT)
Diagnostic Procedure (Cont'd)
EC-489

On Board Diagnosis LogicNBEC0282HThe closed loop control has the one trip detection logic.
Malfunction is detected when the closed loop control function for
right bank does not operate even when vehicle is driving in the
specified condition, the closed loop control function for left bank
does not operate even when vehicle is driving in the specified
condition.
Possible CauseNBEC0531IThe front heated oxygen sensor circuit is open or shorted.
IHeated oxygen sensor 1 (front)
IHeated oxygen sensor 1 heater (front)
DTC Confirmation ProcedureNBEC0283CAUTION:
Always drive vehicle at a safe speed.
NOTE:
If ªDTC Confirmation Procedureº has been previously conducted,
always turn ignition switch ªOFFº and wait at least 10 seconds
before conducting the next test.
TESTING CONDITION:
INever raise engine speed above 3,600 rpm during the
ªDTC Confirmation Procedureº. If the engine speed limit is
exceeded, retry the procedure from step 2.
IBefore performing the following procedure, confirm that
battery voltage is more than 11V at idle.
SEF063Y
WITH CONSULT-IINBEC0283S011) Start engine and warm it up to normal operating temperature.
2) Select ªDATA MONITORº mode with CONSULT-II.
3) Hold engine speed at 2,000 rpm and check one of the follow-
ing.
IªHO2S1 (B1)/(B2)º voltage should go above 0.70V at least
once.
IªHO2S1 (B1)/(B2)º voltage should go below 0.21V at least
once.
If the check result is NG, perform ªDiagnosis Procedureº,
EC-492.
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DTC P1148 (RIGHT BANK, -B1), P1168 (LEFT BANK, -B2) CLOSED LOOP
CONTROL
On Board Diagnosis Logic
EC-491

SEF999Y
Component DescriptionNBEC0532The swirl control valve control vacuum check switch detects
vacuum signal to the swirl control valve, and sends ªONº or ªOFFº
signal to the ECM.
When vacuum is supplied to the valve, the swirl control valve con-
trol vacuum check switch sends ªOFFº signal to the ECM.
The swirl control valve control vacuum check switch is not used to
control the engine system, it is used for on board diagnosis.
SEF446Z
CONSULT-II Reference Value in Data Monitor
Mode
NBEC0533Specification data are reference values.
MONITOR ITEM CONDITION SPECIFICATION
SWL CON VC SWIEngine speed: Idle
IEngine coolant temperature is between 15ÉC (59ÉF) to 50ÉC (122ÉF).OFF
IEngine speed: Idle
IEngine coolant temperature is above 55ÉC (131ÉF).ON
ECM Terminals and Reference ValueNBEC0674Specification 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)
55 W/BSwirl control valve con-
trol vacuum check
switch[Engine is running]
IIdle speed
IEngine coolant temperature is between 15 to
50ÉC (59 to 122ÉF).Approximately 5V
[Engine is running]
IIdle speed
IEngine coolant temperature is above 55ÉC
(122ÉF).0 - 1.0V
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DTC P1165 SWIRL CONTROL VALVE CONTROL VACUUM CHECK SWITCH
Component Description
EC-493