ignition INFINITI QX56 2006 Factory Service Manual

DTC P0327, P0328, P0332, P0333 KSEC-337
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EC
Revision: November 2009 2006 QX56
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 result in dam-
age to the ECM's transistor. Use a ground other than ECM terminals, such as the ground.
Diagnostic ProcedureUBS00H3X
1. CHECK KNOCK SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT-I
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check resistance between ECM terminals 15, 36 and ground. Refer to Wiring Diagram. NOTE:
It is necessary to use an ohmmeter which can measure more than 10 M Ω.
4. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 5.
NG >> GO TO 2.
2. CHECK KNOCK SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT-II
1. Disconnect knock sensor harness connector.
2. Check harness continuity between ECM terminal 15 and knock sensor (bank1) terminal 1, ECM terminal 36 and knock sensor
(bank 2) terminal 1.
Refer to Wiring Diagram.
3. 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.

Harness connectors F26, F101

Harness for open or short between ECM and knock sensor
>> Repair open circuit or short to ground or short to power in harness or connectors.
4. CHECK KNOCK SENSOR
Refer to EC-339, "
Component Inspection" .
OK or NG
OK >> GO TO 5.
NG >> Replace knock sensor.
TER-
MINAL NO. WIRE
COLOR ITEM
CONDITION DATA (DC Voltage)
15
36 W
W Knock sensor (bank 1)
Knock sensor (bank 2) [Engine is running]

Idle speed
Approximately 2.5V
Resistance: Approximately 532 - 588 kΩ
[at 20°C (68 °F)]
Continuity should exist.
PBIB0021E

EC-340Revision: November 2009
DTC P0335 CKP SENSOR (POS)
2006 QX56
DTC P0335 CKP SENSOR (POS)PFP:23731
Component DescriptionUBS00H40
The crankshaft position sensor (POS) is located on the A/T assem-
bly facing the gear teeth (cogs) of the signal plate. It detects the fluc-
tuation of the engine revolution.
The sensor consists of a permanent magnet and Hall IC.
When the engine is running, the high and low parts of the teeth
cause the gap with the sensor to change.
The changing gap causes the magnetic field near the sensor to
change.
Due to the changing magnetic field, the voltage from the sensor
changes.
The ECM receives the voltage signal and detects the fluctuation of
the engine revolution.
ECM receives the signals as shown in the figure.
CONSULT-II Reference Value in Data Monitor ModeUBS00H41
Specification data are reference values.
On Board Diagnosis LogicUBS00H42
DTC Confirmation ProcedureUBS00H43
NOTE:
If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 10.5V with igni-
tion switch ON.
PBIB0562E
PBIB2448E
MONITOR ITEM CONDITION SPECIFICATION
ENG SPEED

Run engine and compare CONSULT-II value with the tachometer indication. Almost the same speed as the
tachometer indication.
DTC No. Trouble diagnosis name
DTC detecting condition Possible cause
P0335
0335 Crankshaft position
sensor (POS) circuit

The crankshaft position sensor (POS) signal
is not detected by the ECM during the first
few seconds of engine cranking.

The proper pulse signal from the crankshaft
position sensor (POS) is not sent to ECM
while the engine is running.

The crankshaft position sensor (POS) signal
is not in the normal pattern during engine
running.

Harness or connectors
(The sensor circuit is open or shorted)

Crankshaft position sensor (POS)

Signal plate

DTC P0335 CKP SENSOR (POS)EC-341
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Revision: November 2009 2006 QX56
WITH CONSULT-II
1. Turn ignition switch ON and select “DATA MONITOR” mode with
CONSULT-II.
2. Crank engine for at least 2 seconds and run it for at least 5 sec- onds at idle speed.
3. If 1st trip DTC is detected, go to EC-343, "
Diagnostic Procedure"
.
WITH GST
Follow the procedure “WITH CONSULT-II” above.
SEF058Y

DTC P0335 CKP SENSOR (POS)EC-343
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EC
Revision: November 2009 2006 QX56
Specification data are reference values and are measured between each terminal and ground.
Pulse signal is measured by CONSULT-II.
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.
: Average voltage for pulse signal (Actual pulse signal can be confirmed by oscilloscope.)
Diagnostic ProcedureUBS00H45
1. CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten three ground screws on the body. Refer to EC-150, "
Ground Inspection" .
OK or NG
OK >> GO TO 2.
NG >> Repair or replace ground connections.
TER-
MINAL NO. WIRE
COLOR ITEM
CONDITION DATA (DC Voltage)
13 O Crankshaft position sensor
(POS) [Engine is running]

Warm-up condition

Idle speed
NOTE:
The pulse cycle changes depending on rpm at
idle. 1.0 - 2.0V
[Engine is running]

Engine speed: 2,000 rpm. 1.0 - 2.0V
111 W / B ECM relay
(Self shut-off) [Engine is running]
[Ignition switch: OFF]

For a few seconds after turning ignition switch
OFF
0 - 1.5V
[Ignition switch: OFF]

More than a few seconds after turning ignition
switch OFF BATTERY VOLTAGE
(11 - 14V)
11 9
120 BR
BR
Power supply for ECM
[Ignition switch: ON] BATTERY VOLTAGE
(11 - 14V)
PBIB1041E
PBIB1042E
BBIA0354E

EC-344Revision: November 2009
DTC P0335 CKP SENSOR (POS)
2006 QX56
2. CHECK CRANKSHAFT POSITION (CKP) SENSOR (POS) POWER SUPPLY CIRCUIT
1. Disconnect crankshaft position (CKP) sensor (POS) harness connector.
2. Turn ignition switch ON.
3. Check voltage between CKP sensor (POS) terminal 3 and ground with CONSULT-II or tester.
OK or NG
OK >> GO TO 4.
NG >> GO TO 3.
3. DETECT MALFUNCTIONING PART
Check the following.

Harness connectors F32, E2

Harness for open or short between crankshaft position sensor (POS) and ECM

Harness for open or short between crankshaft position sensor (POS) and IPDM E/R
>> Repair open circuit or short to ground or short to power in harness or connectors.
4. CHECK CKP SENSOR (POS) GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Check harness continuity between CKP sensor (POS) terminal 1 and ground. Refer to Wiring Diagram.
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.

Harness connectors F32, E2

Harness for open or short between crankshaft position sensor (POS) and ground
>> Repair open circuit or short to power in harness or connectors.
BBIA0367E
Voltage: Battery voltage
SEF481Y
Continuity should exist.

DTC P0340 CMP SENSOR (PHASE)EC-347
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Revision: November 2009 2006 QX56
DTC P0340 CMP SENSOR (PHASE)PFP:23731
Component DescriptionUBS00H48
The camshaft position sensor (PHASE) senses the protrusion of
exhaust valve cam sprocket to identify a particular cylinder. The
camshaft position sensor (PHASE) senses the piston position.
When the crankshaft position sensor (POS) system becomes inoper-
ative, the camshaft position sensor (PHASE) provides various con-
trols of engine parts instead, utilizing timing of cylinder identification
signals.
The sensor consists of a permanent magnet and Hall IC.
When engine is running, the high and low parts of the teeth cause
the gap with the sensor to change.
The changing gap causes the magnetic field near the sensor to
change.
Due to the changing magnetic field, the voltage from the sensor changes.
ECM receives the signals as shown in the figure.
On Board Diagnosis LogicUBS00H49
DTC Confirmation ProcedureUBS00H4A
NOTE:
If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 10.5V with igni-
tion switch ON.
WITH CONSULT-II
1. Turn ignition switch ON.
PBIB0562E
PBIB2448E
DTC No. Trouble diagnosis nameDTC detecting condition Possible cause
P0340
0340 Camshaft position sen-
sor (PHASE) circuit

The cylinder No. signal is not sent to ECM
for the first few seconds during engine
cranking.

The cylinder No. signal is not sent to ECM
during engine running.

The cylinder No. signal is not in the normal
pattern during engine running.

Harness or connectors
(The sensor circuit is open or shorted)

Camshaft position sensor (PHASE)

Camshaft (Exhaust)

Starter motor (Refer to
SC-10, "START-
ING SYSTEM" .)

Starting system circuit (Refer to SC-10,
"STARTING SYSTEM" .)

Dead (Weak) battery

EC-350Revision: November 2009
DTC P0340 CMP SENSOR (PHASE)
2006 QX56
Specification data are reference values and are measured between each terminal and ground.
Pulse signal is measured by CONSULT-II.
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.
: Average voltage for pulse signal (Actual pulse signal can be confirmed by oscilloscope.)
Diagnostic ProcedureUBS00H4C
1. CHECK STARTING SYSTEM
Turn ignition switch to START position.
Ye s o r N o
Yes >> GO TO 2.
No >> Check starting system. (Refer to SC-10, "
STARTING SYSTEM" .)
TER-
MINAL NO. WIRE
COLOR ITEM
CONDITION DATA (DC Voltage)
14 Y Camshaft position sensor
(PHASE) [Engine is running]

Warm-up condition

Idle speed
NOTE:
The pulse cycle changes depending on rpm at
idle. 1.0 - 4.0V
[Engine is running]

Engine speed: 2,000 rpm. 1.0 - 4.0V
111 W / B ECM relay
(Self shut-off) [Engine is running]
[Ignition switch: OFF]

For a few seconds after turning ignition
switch OFF
0 - 1.5V
[Ignition switch: OFF]

More than a few seconds after turning igni-
tion switch OFF BATTERY VOLTAGE
(11 - 14V)
11 9
120 BR
BR
Power supply for ECM
[Ignition switch: ON] BATTERY VOLTAGE
(11 - 14V)
PBIB1039E
PBIB1040E
Does the engine turn over?
Does the starter motor operate?

DTC P0340 CMP SENSOR (PHASE)EC-351
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Revision: November 2009 2006 QX56
2. CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten three ground screws on the body. Refer to EC-150, "
Ground Inspection" .
OK or NG
OK >> GO TO 3.
NG >> Repair or replace ground connections.
3. CHECK CAMSHAFT POSITION (CMP) SENSOR (PHASE) POWER SUPPLY CIRCUIT
1. Disconnect camshaft position (CMP) sensor (PHASE) harness connector.
2. Turn ignition switch ON.
3. Check voltage between CMP sensor (PHASE) terminal 3 and ground with CONSULT-II or tester.
OK or NG
OK >> GO TO 5.
NG >> GO TO 4.
4. DETECT MALFUNCTIONING PART
Check the following.

Harness connectors F32, E2

Harness for open or short between camshaft position sensor (PHASE) and ECM

Harness for open or short between camshaft position sensor (PHASE) and IPDM E/R
>> Repair open circuit or short to ground or short to power in harness or connectors.
BBIA0354E
BBIA0372E
Voltage: Battery voltage
SEF481Y

EC-352Revision: November 2009
DTC P0340 CMP SENSOR (PHASE)
2006 QX56
5. CHECK CMP SENSOR (PHASE) GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Check harness continuity between CMP sensor (PHASE) terminal 1 and ground. Refer to wiring Diagram.
3. Also check harness for short to power.
OK or NG
OK >> GO TO 7.
NG >> GO TO 6.
6. DETECT MALFUNCTIONING PART
Check the following.

Harness connectors F32, E2

Harness for open or short between CMP sensor (PHASE) and ground
>> Repair open circuit or short to power in harness or connectors.
7. CHECK CMP SENSOR (PHASE) INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Disconnect ECM harness connector.
2. Check harness continuity between ECM terminal 14 and CMP sensor (PHASE) terminal 2. Refer to Wiring Diagram.
3. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 8.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
8. CHECK CAMSHAFT POSITION SENSOR (PHASE)
Refer to EC-353, "
Component Inspection" .
OK or NG
OK >> GO TO 9.
NG >> Replace camshaft position sensor (PHASE).
9. CHECK INTERMITTENT INCIDENT
Refer to EC-144, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
>> INSPECTION END
Continuity should exist.
Continuity should exist.

EC-354Revision: November 2009
DTC P0420, P0430 THREE WAY CATALYST FUNCTION
2006 QX56
DTC P0420, P0430 THREE WAY CATALYST FUNCTIONPFP:20905
On Board Diagnosis LogicUBS00H4F
The ECM monitors the switching frequency ratio of air fuel sensor
(A/F) sensor 1 and heated oxygen sensor 2.
A three way catalyst (manifold) with high oxygen storage capacity
will indicate a low switching frequency of heated oxygen sensor 2.
As oxygen storage capacity decreases, the heated oxygen sensor 2
switching frequency will increase.
When the frequency ratio of air fuel ratio (A/F) sensor 1 and heated
oxygen sensor 2 approaches a specified limit value, the three way
catalyst (manifold) malfunction is diagnosed.
DTC Confirmation ProcedureUBS00H4G
NOTE:
If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
WITH CONSULT-II
TESTING CONDITION:
Do not hold engine speed for more than the specified minutes below.
1. Turn ignition switch ON and select “DATA MONITOR” mode with
CONSULT-II.
2. Start engine and warm it up to the normal operating tempera- ture.
3. Turn ignition switch OFF and wait at least 10 seconds.
4. Start engine and keep the engine speed between 3,500 and 4,000 rpm for at least 1 minute under no load.
5. Let engine idle for 1 minute.
6. Make sure that “COOLAN TEMP/S ” indicates more than 70°C
(158 °F).
If not, warm up engine and go to next step when “COOLAN
TEMP/S ” indication reaches to 70 °C (158 °F).
7. Open engine hood.
PBIB2055E
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0420
0420
(Bank 1) Catalyst system effi-
ciency below threshold

Three way catalyst (manifold) does not oper-
ate properly.

Three way catalyst (manifold) does not have
enough oxygen storage capacity.

Three way catalyst (manifold)

Exhaust tube

Intake air leaks

Fuel injector

Fuel injector leaks

Spark plug

Improper ignition timing
P0430
0430
(Bank 2)
SEF189Y