2009 INFINITI QX56 ignition

EC-380
< COMPONENT DIAGNOSIS >[VK56DE]
P2A00, P2A03 A/F SENSOR 1
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
1. Turn ignition switch ON.
2. Check voltage between A/F sensor 1 terminal 4 and ground with CONSULT-IIl or tester.
OK or NG
OK >> GO TO 8.
NG >> GO TO 7.
7.DETECT MALFUNCTIONING PART
Check the following.
 Harness connectors E5, F14
 IPDM E/R harness connector E119
 15A fuse
 Harness for open or short between A/F sensor 1 and fuse
>> Repair or replace harness or connectors.
8.CHECK A/F SENSOR 1 INPUT SIGN AL CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check harness continuity between A/F sensor 1 terminal and ECM terminal as follows.
Refer to Wiring Diagram.
4. Check harness continuity between the following terminals and ground. Refer to Wiring Diagram.Water should not exit.
BBIA0376E
Voltage: Battery voltage
PBIB3308E
A/F sensor 1 terminal ECM terminal
Bank1 135
256
Bank 2 116
275
Continuity should exist.
Revision: December 20092009 QX56

P2A00, P2A03 A/F SENSOR 1EC-381
< COMPONENT DIAGNOSIS > [VK56DE]
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5. Also check harness for short to power.
OK or NG
OK >> GO TO 9.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
9.CHECK A/F SENSOR 1 HEATER
Refer to EC-96, "Component Inspection"
.
OK or NG
OK >> GO TO 10.
NG >> GO TO 11.
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.
Bank 1 Bank 2
A/F sensor 1 terminal ECM terminal A/F sensor 1 terminal ECM terminal 135116
256275
Continuity should not exist.
Revision: December 20092009 QX56

EC-382
< COMPONENT DIAGNOSIS >[VK56DE]
P2A00, P2A03 A/F SENSOR 1
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: December 20092009 QX56

ASCD BRAKE SWITCHEC-383
< COMPONENT DIAGNOSIS > [VK56DE]
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ASCD BRAKE SWITCH
Component DescriptionINFOID:0000000003771703
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:0000000003771704
1.CHECK OVERALL FUNCTION-I
With CONSULT-IIl
1. Turn ignition switch ON.
2. Select “BRAKE SW1” in “DATA 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
CONDITION VOLTAGE
Brake pedal: Slightly depressed Approximately 0V
Brake pedal: Fully released Battery voltage
MBIB0061E
CONDITION INDICATION
Brake pedal: Fully released OFF
Brake pedal: Slightly depressed ON
Revision: December 20092009 QX56

EC-384
< COMPONENT DIAGNOSIS >[VK56DE]
ASCD BRAKE SWITCH
OK or NG
OK >>
INSPECTION END
NG >> GO TO 7.
3.CHECK ASCD BRAKE SWITCH POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect ASCD brake switch harness connector.
3. Turn ignition switch ON.
4. Check voltage between ASCD brake switch terminal 1 and ground with CONSULT-IIl or tester.
OK or NG
OK >> GO TO 5.
NG >> GO TO 4.
4.DETECT MALFUNCTIONING PART
Check the following.
 Harness connectors M31, E152
 Fuse block (J/B) connector M4
 10A fuse
 Harness for open or short between ASCD brake switch and fuse
>> Repair open circuit or short to ground or short to power in harness or connectors.
5.CHECK ASCD BRAKE SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check harness continuity between ECM terminal 108 and ASCD brake switch terminal 2. Refer to Wiring Diagram.
CONDITION VOLTAGE
Brake pedal: Fully released Approximately 0V
Brake pedal: Slightly depressed Battery voltage
PBIB1537E
BBIA0373E
Voltage: Battery voltage
PBIB0857E
Continuity should exist.
Revision: December 20092009 QX56

ASCD BRAKE SWITCHEC-385
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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-386, "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 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 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: December 20092009 QX56

EC-386
< COMPONENT DIAGNOSIS >[VK56DE]
ASCD BRAKE SWITCH
10.CHECK STOP LAMP SWITCH
Refer to EC-386, "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:0000000003771705
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.
Condition Continuity
Brake pedal: Fully released Should exist.
Brake pedal: Slightly depressed Should not exist.
PBIB1536E
Condition Continuity
Brake pedal: Fully released Should not exist.
Brake pedal: Slightly depressed Should exist.
PBIB2103E
Revision: December 20092009 QX56

ASCD INDICATOREC-387
< COMPONENT DIAGNOSIS > [VK56DE]
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ASCD INDICATOR
Component DescriptionINFOID:0000000003771706
ASCD indicator lamp illuminates to indicate ASCD operation status. Lamp has two indicators, CRUISE and
SET, and is integrated in combination meter.
CRUISE indicator illuminates when MAIN switch on ASCD st
eering switch is turned ON to indicate that ASCD
system is ready for operation.
SET indicator illuminates when following conditions are met.
 CRUISE indicator is illuminated.
 SET/COAST switch on ASCD steering switch is tur ned ON while vehicle speed is within the range of ASCD
setting.
SET indicator remains lit during ASCD control.
Refer to EC-33
for the ASCD function.
Diagnosis ProcedureINFOID:0000000003771707
1.CHECK OVERALL FUNCTION
Check ASCD indicator under the following conditions.
OK or NG
OK >> INSPECTION END
NG >> GO TO 2.
2.CHECK DTC
Check that DTC U1000 or U1001 is not displayed.
OK or NG
OK >> GO TO 3.
NG >> Perform trouble diagnosis for DTC U1000, U1001. Refer to EC-86
.
3.CHECK COMBINATION METER FUNCTION
Refer to MWI-5
.
OK or NG
OK >> GO TO 4.
NG >> Go to MWI-5
.
4.CHECK INTERMITTENT INCIDENT
Refer to GI-35, "How to Check Terminal"
and GI-38, "Intermittent Incident".
>> INSPECTION END
ASCD INDICATOR CONDITION SPECIFICATION
CRUISE LAMP  Ignition switch: ON  MAIN switch: Pressed at the 1st
time → at the 2nd time ON
→ OFF
SET LAMP  MAIN switch: ON
 When vehicle speed is between
40 km/h (25 MPH) and 144 km/h
(89 MPH) ASCD: Operating ON
 ASCD: Not operating OFF
Revision: December 20092009 QX56