Stop INFINITI QX56 2008 Factory Service Manual

EC-386
< COMPONENT DIAGNOSIS >[VK56DE]
P2A00, P2A03 A/F SENSOR 1
8. Keep engine speed between 2,500 and 3,000 rpm for 20 minutes.
9. Check 1st trip DTC.
10. If 1st trip DTC is detected, go to
EC-386, "
Diagnosis Procedure".
WITH GST
1. Start engine and warm it up to normal operating temperature.
2. Turn ignition switch OFF and wait at least 10 seconds.
3. Disconnect mass air flow sensor harness connector.
4. Start engine and let it idle for at least 5 seconds.
5. Stop engine and reconnect mass air flow sensor harness con-
nector.
6. Select Service $03 with GST and make sure that DTC P0102 is detected.
7. Select Service $04 with GST and erase the DTC P0102.
8. Start engine and keep the engine speed between 3,500 and 4,000 rpm for 1 minute under no load.
9. Let engine idle for 1 minute.
10. Keep engine speed between 2,500 and 3,000 rpm for 20 min- utes.
11. Select Service $07 with GST. If 1st trip DTC is detected, go to EC-386, "
Diagnosis Procedure".
Diagnosis ProcedureINFOID:0000000001365861
1.CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten two ground screws on the body. Refer to EC-86, "
Ground Inspection".
OK or NG
OK >> GO TO 2.
NG >> Repair or replace ground connections.
2.RETIGHTEN A/F SENSOR 1
1. Loosen and retighten the A/F sensor 1.
BBIA0368E
BBIA0354E
Tightening torque: 50 N-m (5.1 kg-m, 37 ft-lb)
BBIA0375E
Revision: March 2010 2008 QX56

P2A00, P2A03 A/F SENSOR 1EC-387
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>> GO TO 3.
3.CHECK FOR INTAKE AIR LEAK
1. Start engine and run it at idle.
2. Listen for an intake air leak after the mass air flow sensor.
OK or NG
OK >> GO TO 4.
NG >> Repair or replace.
4.CLEAR THE SELF-LEARNING DATA
With CONSULT-IIl
1. Start engine and warm it up to normal operating temperature.
2. Select “SELF-LEARNING CONT” in “W ORK SUPPORT” mode with CONSULT-IIl.
3. Clear the self-learning control coefficient by touching “CLEAR”.
4. Run engine for at least 10 minutes at idle speed. Is the 1st trip DTC P0171, P0172, P0174 or P0175 detected?
Is it difficult to start engine?
Without CONSULT-IIl
1. Start engine and warm it up to normal operating temperature.
2. Turn ignition switch OFF.
3. Disconnect mass air flow sensor harness connector.
4. Restart engine and let it idle for at least 5 seconds.
5. Stop engine and reconnect mass air flow sensor harness con-
nector.
6. Make sure DTC P0102 is displayed.
7. Erase the DTC memory. Refer to EC-462, "
DTC Index".
8. Make sure DTC P0000 is displayed.
9. Run engine for at least 10 minutes at idle speed. Is the 1st trip DTC P0171, P0172, P0174 or P0175 detected?
Is it difficult to start engine?
Ye s o r N o
Yes >> Perform trouble diagnos is for DTC P0171, P0174 or
P0172, P0175. Refer to EC-176
or EC-182.
No >> GO TO 5.
5.CHECK HARNESS CONNECTOR
1. Turn ignition switch OFF.
2. Disconnect A/F sensor 1 harness connector.
3. Check harness connector for water.
OK or NG
OK >> GO TO 6.
NG >> Repair or replace harness connector.
6.CHECK A/F SENSOR 1 POWER SUPPLY CIRCUIT
BBIA0368E
Water should not exit.
BBIA0376E
Revision: March 2010 2008 QX56

P2A00, P2A03 A/F SENSOR 1EC-389
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10.CHECK INTERMITTENT INCIDENT
Perform GI-35, "
How to Check Terminal" and GI-38, "Intermittent Incident".
OK or NG
OK >> GO TO 11.
NG >> Repair or replace.
11 .REPLACE AIR FUEL RATIO (A/F) SENSOR 1
Replace malfunctioning air f uel ratio (A/F) sensor 1.
CAUTION:
• Discard any A/F sensor which has been dropped from a height of more than 0.5 m (19.7 in) onto a
hard surface such as a concrete floor; use a new one.
• Before installing new A/F senso r, clean exhaust system threads using Oxygen Sensor Thread
Cleaner tool J-43897-18 or J-43897-12 and approved anti-seize lubricant.
>> GO TO 12.
12.CONFIRM A/F ADJUSTMENT DATA
1. Turn ignition switch OFF and then ON.
2. Select “A/F ADJ-B1” and “” in “DATA MONITOR” mode with CONSULT-lll.
3. Make sure that “0.000” is displayed on CONSULT-lll screen.
OK or NG
OK >> INSPECTION END
NG >> GO TO 13.
13.CLEAR THE SELF-LEARNING DATA
With CONSULT-lll
1. Start engine and warm it up to normal operating temperature.
2. Select “SELF-LEARNING CONT” in “WORK SUPPORT” mode with CONSULT-lll.
3. Clear the self-learning control coefficient by touching “CLEAR”.
Without CONSULT-lll
1. Start engine and warm it up to normal operating temperature.
2. Turn ignition switch OFF.
3. Disconnect mass air flow sensor harness connector.
4. Restart engine and let it idle for at least 5 seconds.
5. Stop engine and reconnect mass air flow sensor harness con- nector.
6. Make sure DTC P0102 is displayed.
7. Erase the DTC memory. Refer to EC-55, "
Malfunction Indicator
Lamp (MIL)".
8. Make sure DTC P0000 is displayed.
>> GO TO 14.
14.CONFIRM A/F ADJUSTMENT DATA
1. Turn ignition switch OFF and then ON.
2. Select “A/F ADJ-B1” and “A/F ADJ-B2” in “DATA MONITOR” mode with CONSULT-IIl.
3. Make sure that “0.000” is displayed on CONSULT-IIl screen.
>>INSPECTION END
BBIA0368E
Revision: March 2010 2008 QX56

EC-390
< COMPONENT DIAGNOSIS >[VK56DE]
ASCD BRAKE SWITCH
ASCD BRAKE SWITCH
Component DescriptionINFOID:0000000001365863
When the brake pedal is depressed, ASCD brake switch is turned
OFF and stop lamp switch is turned ON. ECM detects the state of
the brake pedal by this input of two kinds (ON/OFF signal).
Refer to
EC-33
for the ASCD function.
Diagnosis ProcedureINFOID:0000000001365866
1.CHECK OVERALL FUNCTION-I
With CONSULT-IIl
1. Turn ignition switch ON.
2. Select “BRAKE SW1” in “DAT A MONITOR” mode with CONSULT-IIl.
3. Check “BRAKE SW1” indication under the following conditions.
Without CONSULT-IIl
1. Turn ignition switch ON.
2. Check voltage between ECM terminal 108 and ground under the
following conditions.
OK or NG
OK >> GO TO 2.
NG >> GO TO 3.
2.CHECK OVERALL FUNCTION-II
With CONSULT-IIl
Check “BRAKE SW2” indication in “DATA MONITOR” mode.
Without CONSULT-IIl
Check voltage between ECM terminal 101 and ground under the following conditions.
BBIA0373E
CONDITION INDICATION
Brake pedal: Slightly depressed OFF
Brake pedal: Fully released ON
CONDITIONVOLTAGE
Brake pedal: Slightly depressed Approximately 0V
Brake pedal: Fully released Battery voltage
MBIB0061E
CONDITIONINDICATION
Brake pedal: Fully released OFF
Brake pedal: Slightly depressed ON
Revision: March 2010 2008 QX56

EC-392
< COMPONENT DIAGNOSIS >[VK56DE]
ASCD BRAKE SWITCH
4. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 6.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
6.CHECK ASCD BRAKE SWITCH
Refer to EC-393, "
Component Inspection".
OK or NG
OK >> GO TO 11.
NG >> Replace ASCD brake switch.
7.CHECK STOP LAMP SWIT CH POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect stop lamp switch harness connector.
3. Check voltage between stop lamp switch terminal 3 and ground with CONSULT -IIl or tester.
OK or NG
OK >> GO TO 9.
NG >> GO TO 8.
8.DETECT MALFUNCTIONING PART
Check the following.
• Harness connectors M31, E152
• Fuse block (J/B) connector M60
• 10A fuse
• Harness for open or short between stop lamp switch and battery
>> Repair open circuit or short to ground or short to power in harness or connectors.
9.CHECK STOP LAMP SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Disconnect ECM harness connector.
2. Check harness continuity between ECM terminal 101 and stop lamp switch terminal 4. Refer to Wiring Diagram.
3. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 10.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
BBIA0373E
Voltage: Battery voltage
PBIB2102E
Continuity should exist.
Revision: March 2010 2008 QX56

ASCD BRAKE SWITCHEC-393
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10.CHECK STOP LAMP SWITCH
Refer to EC-393, "
Component Inspection".
OK or NG
OK >> GO TO 11.
NG >> Replace stop lamp switch.
11 .CHECK INTERMITTENT INCIDENT
Refer to GI-35, "
How to Check Terminal" and GI-38, "Intermittent Incident".
>> INSPECTION END
Component InspectionINFOID:0000000001365867
ASCD BRAKE SWITCH
1. Turn ignition switch OFF.
2. Disconnect ASCD brake switch harness connector.
3. Check harness continuity between ASCD brake switch terminals
1 and 2 under the following conditions.
If NG, adjust ASCD brake switch installation, refer to BR-15,
"Inspection and Adjustment", and perform step 3 again.
STOP LAMP SWITCH
1. Turn ignition switch OFF.
2. Disconnect stop lamp switch harness connector.
3. Check harness continuity between stop lamp switch terminals 3
and 4 under the following conditions.
If NG, adjust stop lamp switch installation, refer to BR-15,
"Inspection and Adjustment", and perform step 3 again.
ConditionContinuity
Brake pedal: Fully released Should exist.
Brake pedal: Slightly depressed Should not exist.
PBIB1536E
ConditionContinuity
Brake pedal: Fully released Should not exist.
Brake pedal: Slightly depressed Should exist.
PBIB2103E
Revision: March 2010 2008 QX56

EC-402
< COMPONENT DIAGNOSIS >[VK56DE]
FUEL PUMP
FUEL PUMP
DescriptionINFOID:0000000001365881
SYSTEM DESCRIPTION
*: ECM determines the start signal status by the signals of engine speed and battery voltage.
The ECM activates the fuel pump for several seconds after the ignition switch is turned ON to improve engine
startability. If the ECM receives a engine speed signal
from the camshaft position sensor (PHASE), it knows
that the engine is rotating, and causes the pump to operate. If the engine speed signal is not received when
the ignition switch is ON, the engine stalls. The EC M stops pump operation and prevents battery discharging,
thereby improving safety. The ECM does not directly drive the fuel pump. It controls the ON/OFF fuel pump
relay, which in turn controls the fuel pump.
COMPONENT DESCRIPTION
A turbine type design fuel pump is used in the fuel tank.
Diagnosis ProcedureINFOID:0000000001365884
1.CHECK OVERALL FUNCTION
1. Turn ignition switch ON.
2. Pinch fuel feed hose with two fingers.
OK or NG
OK >> INSPECTION END
NG >> GO TO 2.
2.CHECK FUEL PUMP POWER SUPPLY CIRCUIT-I
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Turn ignition switch ON.
Sensor Input signal to ECMECM FunctionActuator
Crankshaft position sensor (POS)
Camshaft position sensor (PHASE) Engine speed*
Fuel pump control Fuel pump relay
Battery Battery voltage*
Condition Fuel pump operation
Ignition switch is turned to ON. Operates for 1 second.
Engine running and cranking Operates.
When engine is stopped Stops in 1.5 seconds.
Except as shown above Stops.
BBIA0402E
Fuel pressure pulsation should be felt on the fuel feed
hose for 1 second after igniti on switch is turned ON.
BBIA0357E
Revision: March 2010 2008 QX56

EC-406
< COMPONENT DIAGNOSIS >[VK56DE]
ICC BRAKE SWITCH
ICC BRAKE SWITCH
Component DescriptionINFOID:0000000001365887
When depress on the brake pedal, ICC brake switch is turned OFF
and stop lamp switch is turned ON. ECM detects the state of the
brake pedal by this input of two kinds (ON/OFF signal)
Refer to
CCS-13
for the ICC function.
Diagnosis ProcedureINFOID:0000000001365890
1.CHECK OVERALL FUNCTION-I
With CONSULT-IIl
1. Turn ignition switch ON.
2. Select “BRAKE SW1” in “DAT A MONITOR” mode with CONSULT-IIl.
3. Check “BRAKE SW1” indication under the following conditions.
Without CONSULT-IIl
1. Turn ignition switch ON.
2. Check voltage between ECM terminal 108 and ground under the
following conditions.
OK or NG
OK >> GO TO 2.
NG >> GO TO 3.
2.CHECK OVERALL FUNCTION-II
With CONSULT-IIl
Check “BRAKE SW2” indication in “DATA MONITOR” mode.
Without CONSULT-IIl
BBIA0470E
CONDITION INDICATION
Brake pedal: Slightly depressed OFF
Brake pedal: Fully released ON
CONDITIONVOLTAGE
Brake pedal: Slightly depressed Approximately 0V
Brake pedal: Fully released Battery voltage
MBIB0061E
CONDITIONINDICATION
Brake pedal: Fully released OFF
Brake pedal: Slightly depressed ON
Revision: March 2010 2008 QX56

EC-408
< COMPONENT DIAGNOSIS >[VK56DE]
ICC BRAKE SWITCH
1. Turn ignition switch OFF.
2. Disconnect ICC brake switch harness connector.
3. Check harness continuity between ICC brake hold relay terminal
3 and ICC brake switch terminal 1.
Refer to Wiring Diagram.
4. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 7.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
7.CHECK ICC BRAKE SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Disconnect ECM harness connector.
2. Check harness continuity between ICC brake switch terminal 2 and ECM terminal 108. Refer 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 ICC BRAKE HOLD RELAY
Refer to EC-409, "
Component Inspection".
OK >> GO TO 9.
NG >> Replace ICC brake hold relay.
9.CHECK ICC BRAKE SWITCH
Refer to EC-409, "
Component Inspection".
OK or NG
OK >> GO TO 14.
NG >> Replace ICC brake switch.
10.CHECK STOP LAMP SWITCH POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect stop lamp switch harness connector. Continuity should exist.
BBIA0470E
Continuity should exist.
BBIA0470E
Revision: March 2010
2008 QX56

ICC BRAKE SWITCHEC-409
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3. Check voltage between stop lamp switch terminal 3 and ground
with CONSULT -IIl or tester.
OK or NG
OK >> GO TO 12.
NG >> GO TO 11.
11 .DETECT MALFUNCTIONING PART
Check the following.
• Harness connectors M31, E152
• Fuse block (J/B) No. 1 connector M60
• 10A fuse
• Harness for open or short between stop lamp switch and battery
>> Repair open circuit or short to ground or short to power in harness or connectors.
12.CHECK STOP LAMP SWITCH INPUT SI GNAL CIRCUIT FOR OPEN AND SHORT
1. Disconnect ECM harness connector.
2. Check harness continuity between ECM terminal 101 and stop lamp switch terminal 4. Refer to Wiring Diagram.
3. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 13.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
13.CHECK STOP LAMP SWITCH
Refer to EC-409, "
Component Inspection".
OK or NG
OK >> GO TO 14.
NG >> Replace stop lamp switch.
14.CHECK INTERMITTENT INCIDENT
Refer to GI-35, "
How to Check Terminal" and GI-38, "Intermittent Incident".
>> INSPECTION END
Component InspectionINFOID:0000000001365891
ICC BRAKE SWITCH
1. Turn ignition switch OFF.
2. Disconnect ICC brake switch harness connector. Voltage: Battery voltage
PBIB2102E
Continuity should exist.
Revision: March 2010
2008 QX56