engine INFINITI QX4 2001 Factory Service Manual
[x] Cancel search | Manufacturer: INFINITI, Model Year: 2001, Model line: QX4, Model: INFINITI QX4 2001Pages: 2395, PDF Size: 43.2 MB
Page 1043 of 2395

12 CHECK IGNITION COIL POWER SUPPLY CIRCUIT-V
1. Turn ignition switch OFF.
2. Reconnect harness connectors disconnected.
3. Disconnect ignition coil harness connector.
SEF975Y
4. Turn ignition switch ON.
5. Check voltage between ignition coil terminal 3 and ground with CONSULT-II or tester.
SEF370X
OK or NG
OK©GO TO 14.
NG©GO TO 13.
13 DETECT MALFUNCTIONING PART
Check the harness for open or short between ignition coil and harness connector F22.
©Repair or replace harness or connectors.
14 CHECK IGNITION COIL GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Check harness continuity between ignition coil terminal 2 and engine ground. Refer to Wiring Diagram.
Continuity should exist.
3. Also check harness for short to power.
OK or NG
OK©GO TO 15.
NG©Repair open circuit or short to power in harness or connectors.
DTC P1320 IGNITION SIGNAL
Diagnostic Procedure (Cont'd)
EC-508
Page 1045 of 2395

SEF253P
Component DescriptionNBEC0573The crankshaft position sensor (REF) is located on the oil pan
(upper) facing the crankshaft pulley. It detects the TDC (Top Dead
Center) signal (120É signal).
The sensor consists of a permanent magnet, core and coil.
When engine is running, the gap between the sensor and the
crankshaft pulley will periodically change. Permeability near the
sensor also changes.
Due to the permeability change, the magnetic flux near the core is
changed. Therefore, the voltage signal generated in the coil is
changed.
The ECM receives the voltage signal and detects the TDC signal
(120É signal).
CONSULT-II Reference Value in Data Monitor
Mode
NBEC0574Specification data are reference values.
MONITOR ITEM CONDITION SPECIFICATION
CKPS´RPM (POS)ITachometer: Connect
IRun engine and compare tachometer indication with the CONSULT-II
value.Almost the same speed as the
CONSULT-II value.
ENG SPEED
ECM Terminals and Reference ValueNBEC0676Specification 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)
65
75LG
LGCrankshaft position
sensor (REF)[Engine is running]
IWarm-up condition
IIdle speedApproximately 2.3VH
(AC voltage)
SEF581X
H: Average voltage for pulse signal (Actual pulse signal can be confirmed by oscilloscope.)
DTC P1335 CRANKSHAFT POSITION SENSOR (CKPS) (REF)
Component Description
EC-510
Page 1046 of 2395

On Board Diagnosis LogicNBEC0576Malfunction is detected when
(Malfunction A)120É signal is not entered to ECM for the first few
seconds during engine cranking,
(Malfunction B)120É signal is not entered to ECM during engine
running,
(Malfunction C)120É signal cycle excessively changes during
engine running.
FAIL-SAFE MODENBEC0576S01When the ECM enters the fail-safe mode, the MIL illuminates.
Detected items Engine operating condition in fail-safe mode
Crankshaft position sensor (REF)
circuitCompression TDC signal (120É signal) is controlled by camshaft position sensor (PHASE)
signal and crankshaft position sensor (POS) signal. Ignition timing will be delayed 0É to 2É.
Possible CauseNBEC0577IHarness or connectors
(The crankshaft position sensor (REF) circuit is open or
shorted.)
ICrankshaft position sensor (REF)
IStarter motor (Refer to SC section.)
IStarting system circuit (Refer to SC section.)
IDead (Weak) battery
DTC Confirmation ProcedureNBEC0578NOTE:
IPerform ªPROCEDURE FOR MALFUNCTION Aº first. If 1st
trip DTC cannot be confirmed, perform ªPROCEDURE
FOR MALFUNCTION B AND Cº.
IIf 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:
Before performing the following procedure, confirm that bat-
tery voltage is more than 10.5V at idle.
SEF013Y
PROCEDURE FOR MALFUNCTION ANBEC0578S01With CONSULT-IINBEC0578S01011) Turn ignition switch ªONº.
2) Select ªDATA MONITORº mode with CONSULT-II.
3) Crank engine for at least 2 seconds.
4) If 1st trip DTC is detected, go to ªDiagnostic Procedureº,
EC-514.
With GSTNBEC0578S0102Follow the procedure ªWith CONSULT-IIº above.
GI
MA
EM
LC
FE
AT
TF
PD
AX
SU
BR
ST
RS
BT
HA
SC
EL
IDX
DTC P1335 CRANKSHAFT POSITION SENSOR (CKPS) (REF)
On Board Diagnosis Logic
EC-511
Page 1047 of 2395

SEF058Y
PROCEDURE FOR MALFUNCTION B AND CNBEC0578S02With CONSULT-IINBEC0578S02011) Turn ignition switch ªONº.
2) Select ªDATA MONITORº mode with CONSULT-II.
3) Start engine and run it for at least 2 seconds at idle speed.
4) If 1st trip DTC is detected, go to ªDiagnostic Procedureº,
EC-514.
With GSTNBEC0578S0202Follow the procedure ªWith CONSULT-IIº above.
DTC P1335 CRANKSHAFT POSITION SENSOR (CKPS) (REF)
DTC Confirmation Procedure (Cont'd)
EC-512
Page 1049 of 2395

Diagnostic ProcedureNBEC0580
1 RETIGHTEN GROUND SCREWS
1. Turn ignition switch ªOFFº.
2. Loosen and retighten engine ground screws.
SEF959Y
©GO TO 2.
2 CHECK CKPS (REF) INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Disconnect CKPS (REF) harness connector.
SEF011Z
2. Disconnect ECM harness connector.
3. Check harness continuity between ECM terminals 65, 75 and CKPS (REF) terminal 2. 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 4.
NG©GO TO 3.
3 DETECT MALFUNCTIONING PART
Check the following.
IHarness connectors E132, E135
IHarness connectors E116, M114 and M32, F23
IHarness for open or short between crankshaft position sensor (REF) and ECM
©Repair open circuit or short to ground or short to power in harness or connectors.
DTC P1335 CRANKSHAFT POSITION SENSOR (CKPS) (REF)
Diagnostic Procedure
EC-514
Page 1050 of 2395

4 CHECK CKPS (REF) GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch ªOFFº.
2. Check harness continuity between CKPS (REF) terminal 1 and engine ground.
Continuity should exist.
3. Also check harness for short to power.
OK or NG
OK©GO TO 6.
NG©GO TO 5.
5 DETECT MALFUNCTIONING PART
Check the following.
IHarness connectors E132, E135
IHarness connectors E116, M114 and M32, F23
IHarness for open between crankshaft position sensor (REF) and engine ground
©Repair open circuit or short to power in harness or connector.
6 CHECK CKPS (REF)-I
1. Loosen the fixing bolts and remove the CKPS (REF).
2. Visually check the CKPS (REF) for chipping.
SEF585P
OK or NG
OK©GO TO 7.
NG©Replace crankshaft position sensor (REF).
7 CHECK CKPS (REF)-II
Check resistance between CKPS (REF) terminals 1 and 2.
SEF350X
OK or NG
OK©GO TO 8.
NG©Replace crankshaft position sensor (REF).
GI
MA
EM
LC
FE
AT
TF
PD
AX
SU
BR
ST
RS
BT
HA
SC
EL
IDX
DTC P1335 CRANKSHAFT POSITION SENSOR (CKPS) (REF)
Diagnostic Procedure (Cont'd)
EC-515
Page 1051 of 2395

8 CHECK CKPS (REF) SHIELD CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch ªOFFº.
2. Disconnect harness connectors E132, E135.
3. Check harness continuity between harness connector E135 terminal 7 and engine ground.
Continuity should exist.
4. Also check harness for short to power.
OK or NG
OK©GO TO 10.
NG©GO TO 9.
9 DETECT MALFUNCTIONING PART
Check the following.
IHarness connectors E132, E135
IHarness connectors E116, M114 and M32, F23
IHarness for open between harness connector F23 and engine ground
©Repair open circuit or short to power in harness or connectors.
10 CHECK INTERMITTENT INCIDENT
Refer to ªTROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENTº, EC-140.
©INSPECTION END
DTC P1335 CRANKSHAFT POSITION SENSOR (CKPS) (REF)
Diagnostic Procedure (Cont'd)
EC-516
Page 1052 of 2395

SEF977Y
Component DescriptionNBEC0292The crankshaft position sensor (POS) is located on the oil pan
facing the gear teeth (cogs) of the signal plate (flywheel). It detects
the crankshaft position signal (1É signal).
The sensor consists of a permanent magnet, core and coil.
When engine is running, the gap between the sensor and the gear
teeth (cogs) will periodically change. Permeability near the sensor
also changes.
Due to the permeability change, the magnetic flux near the core is
changed. Therefore, the voltage signal generated in the coil is
changed.
The ECM receives the voltage signal and detects the crankshaft
position signal (1É signal).
CONSULT-II Reference Value in Data Monitor
Mode
NBEC0581Specification data are reference values.
MONITOR ITEM CONDITION SPECIFICATION
CKPS´RPM (POS)ITachometer: Connect
IRun engine and compare tachometer indication with the CONSULT-II
value.Almost the same speed as the
CONSULT-II value.
ENG SPEED
GI
MA
EM
LC
FE
AT
TF
PD
AX
SU
BR
ST
RS
BT
HA
SC
EL
IDX
DTC P1336 CRANKSHAFT POSITION SENSOR (CKPS) (POS) (COG)
Component Description
EC-517
Page 1053 of 2395

ECM Terminals and Reference Value=NBEC0677Specification 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)
85 YCrankshaft position
sensor (POS)[Engine is running]
IIdle speedApproximately 2.4V
SEF057V
[Engine is running]
IEngine speed is 2,000 rpm.Approximately 2.3V
SEF058V
On Board Diagnosis LogicNBEC0294Malfunction is detected when chipping of the signal plate (flywheel
or drive plate) gear tooth (cog) is detected by the ECM.
Possible CauseNBEC0582IHarness or connectors
ICrankshaft position sensor (POS)
ISignal plate (Drive plate/Flywheel)
DTC P1336 CRANKSHAFT POSITION SENSOR (CKPS) (POS) (COG)
ECM Terminals and Reference Value
EC-518
Page 1054 of 2395

DTC Confirmation ProcedureNBEC0295NOTE:
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:
Before performing the following procedure, confirm that bat-
tery voltage is more than 10.5V.
SEF058Y
WITH CONSULT-IINBEC0295S011) Turn ignition switch ªONº and select ªDATA MONITORº mode
with CONSULT-II.
2) Start engine and run it for at least 70 seconds at idle speed.
3) If 1st trip DTC is detected, go to ªDiagnostic Procedureº,
EC-521.
WITH GSTNBEC0295S02Follow the procedure ªWITH CONSULT-IIº above.
GI
MA
EM
LC
FE
AT
TF
PD
AX
SU
BR
ST
RS
BT
HA
SC
EL
IDX
DTC P1336 CRANKSHAFT POSITION SENSOR (CKPS) (POS) (COG)
DTC Confirmation Procedure
EC-519