2011 INFINITI QX56 brake

ECM
EC-95
< ECU DIAGNOSIS INFORMATION > [VK56VD]
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P062B ECM Type1
 Engine torque is limited.
 Idle engine speed is increased.
 Fuel injector power supply shut-off.
 High fuel pressure limitation.
Typ e2
 Engine torque is limited.
 Fuel injection shut-off of malfunction cylinder.
 Mixture ratio feedback control does not function.
 Idle engine speed is increased.
P0643 Sensor power supply ECM stops the electric throttle control actuator control, throttle valve is maintained at a
fixed opening (approx. 5 degrees) by the return spring.
P1087
P1088 VVEL control function VVEL of no
rmal bank is controlled at VVEL angle of abnormal bank.
Engine speed will not rise more than 3,500 rpm due to the fuel cut.
P1089
P1092 VVEL control shaft position
sensor VVEL value is maintained at a fixed angle.
Engine speed will not rise more than 3,500 rpm due to the fuel cut
P1197 Out of gas  Engine torque is limited.
 VVEL value is maintained at a fixed angle.
P1608 VVEL control shaft position
sensor VVEL actuator motor relay is turned off, an
d VVEL value is become at a minimum angle.
Engine speed will not rise more than 3,500 rpm due to the fuel cut.
P1090
P1093 VVEL actuator motor VVEL of no
rmal bank is controlled at VVEL angle of abnormal bank.
Engine speed will not rise more than 3,500 rpm due to the fuel cut.
VVEL actuator motor relay is turned off, an d VVEL value is become at a minimum angle.
Engine speed will not rise more than 3,500 rpm due to the fuel cut.
P1091 VVEL actuator motor rela
y VVEL actuator motor relay is turned off, an d VVEL value is become at a minimum angle.
Engine speed will not rise more than 3,500 rpm due to the fuel cut.
P1197 Out of gas  Engine torque is limited.
 VVEL value is maintained at a fixed angle.
P2101 Electric throttle control
function ECM stops the electric throttle control actuator control, throttle valve is maintained at a
fixed opening (approx. 5 degrees) by the return spring.
P2118 Throttle control motor ECM stops the electric throttle control actuator control, throttle valve is maintained at a
fixed opening (approx. 5 degrees) by the return spring.
P2119 Electric throttle control ac-
tuator
(When electric throttle control actuator does not function properly due to the return spring
malfunction:)
ECM controls the electric throttle actuator by regulating the throttle opening around the
idle position. The engine speed will not rise more than 2,000 rpm.
(When throttle valve opening angle in fail-safe mode is not in specified range:)
ECM controls the electric throttle control actuator because of regulating the throttle open-
ing to 20 degrees or less.
(When ECM detects the throttle valve is stuck open:)
While the vehicle is being driven, it slows down gradually by fuel cut. After the vehicle
stops, the engine stalls.
The engine can restart in the N or P position, and engine speed will not exceed 1,000 rpm
or more.
P1290
P2100
P2103 Throttle control motor relay ECM stops the electric throttle control actuator control, throttle valve is maintained at a
fixed opening (approx. 5 degrees) by the return spring.
P1606 VVEL control module VVEL
actuator motor relay is turned off, and VVEL value is become at a minimum angle.
Engine speed will not rise more than 3,500 rpm due to the fuel cut.
P1805 Brake switch ECM controls the electric throttle control
actuator by regulating the throttle opening to a
small range.
Therefore, acceleration will be poor.
Vehicle condition Driving condition
When engine is idling Normal
When accelerating Poor acceleration
DTC No. Detected items Engine operating condition in fail-safe mode
Revision: 2010 May2011 QX56

EC-98
< ECU DIAGNOSIS INFORMATION >[VK56VD]
ECM
NOTE:
*: If “P1197” is displayed with other DTC in priority 1, perform trouble diagnosis for “P1197” first.
DTC IndexINFOID:0000000006217733
×
:Applicable —: Not applicable
2  P0031 P0032 P0051 P0052 Air fuel ratio (A/F) sensor 1 heater
 P0037 P0038 P0057 P0058 Heated oxygen sensor 2 heater
 P0075 P0081 Intake valve timing control solenoid valve
 P0130 P0131 P0132 P0133 P0150 P0151 P0152 P015 3 P2A00 P2A03 Air fuel ratio (A/F) sensor 1
 P0137 P0138 P0139 P0157 P0158 P0159 Heated oxygen sensor 2
 P0190 - P0193 FRP sensor
 P0441 EVAP control system purge flow monitoring
 P0443 P0444 P0445 EVAP canister purge volume control solenoid valve
 P0447 P0448 EVAP canister vent control valve
 P0451 P0452 P0453 EVAP control system pressure sensor
 P0550 Power steering pressure sensor
 P0603 ECM power supply
 P0710 P0717 P0720 P0729 P0730 P0731 P0732 P0733 P0734 P0735 P0740 P0744 P0745 P0750 P0775 P0780 P0795 P1730 P1734 P2713 P2722 P2731 P2807 A/T related sensors, solenoid valves and switches
 P1087 P1088 VVEL system
 P1090 P1093 VVEL actuator motor
 P1091 VVEL actuat or motor relay
 P1217 Engine over temperature (OVERHEAT)
 P1650 Starter motor relay 2
 P1651 Starter motor relay
 P2101 Electric throttle control function
 P2118 Throttle control motor
 P1805 Brake switch
 P2100 P2103 Throttle control motor relay
 P2101 Electric throttle control function
3  P0011 P0021 Intake valve timing control  P0087, P0088, P0090 FRP control system
 P008A Low fuel pressure control system
 P008B Low fuel pressure control system
 P0171 P0172 P0174 P0175 Fuel injection system function
 P0201 - P0208 Injector
 P0300 - P0308 Misfire
 P0420 P0430 Three way catalyst function
 P0456 EVAP control system (VERY SMALL LEAK)
 P0506 P0507 Idle speed control system
 P050E Cold start control
 P0524 Engine oil pressure
 P1148 P1168 Closed loop control
 P1212 TCS communication line
 P1421 Cold start control
 P1564 ASCD steering switch / ICC steering switch
 P1652 Starter motor system communication
 P2119 Electric throttle control actuator
 P1564 ASCD steering switch / ICC steering switch
 P1568 ICC command value
 P1572 ASCD brake switch / ICC brake switch
 P1574 ASCD vehicle speed sensor / ICC vehicle speed sensor
Priority Detected items (DTC)
DTC*1
Items
(CONSULT-III screen terms) SRT code Trip MIL
Reference
page
CONSULT-III
GST*
2ECM*3
U0101 0101 LOST COMM (TCM) — 1 ×EC-171
U0113 0113 CAN COMM CIRCUIT — 1 ×EC-173
U1001
1001*4CAN COMM CIRCUIT — 1 or 2 — EC-172
U1003 1003 CAN COMM CIRCUIT — 2 — EC-173
Revision: 2010 May2011 QX56

ECM
EC-103
< ECU DIAGNOSIS INFORMATION > [VK56VD]
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*1: 1st trip DTC No. is
the same as DTC No.
P1572 1572 ASCD BRAKE SW — 1 —
EC-438
(with ASCD)
EC-443
(with ICC)
P1574 1574 ASCD VHL SPD SEN — 1 — EC-447
(with ASCD)
EC-449
(with ICC)
P1606 1606 VVEL CONTROL MODULE — 1 or 2 × or — EC-451
P1607 1607 VVEL CONTROL MODULE — 1 ×EC-452
P1608 1608 VVEL SENSOR POWER/CIRC — 1 ×EC-453
P1610 1610 LOCK MODE — 2 — SEC-53
P1611 1611 ID DISCORD IMMU-ECM — 2 —SEC-54
P1612 1612 CHAIN OF ECM-IMMU — 2 — SEC-55
P1613 1613 ECM INT CIRC-IMMU — 2 —SEC-48
P1614 1614 CHAIN OF IMMU-KEY — 2 —SEC-56
P1615 1615 DIFFERENCE OF KEY — 2 —SEC-48
P1650 1650 STR MTR RELAY 2 — 2×SEC-48
P1651 1651 STR MTR RELAY — 2 ×SEC-48
P1652 1652 STR MTR SYS COMM — 1 ×SEC-48
P1730 1730 INTERLOCK — 2 ×TM-140
P1734 1734
7GR INCORRECT RATIO*7—2 ×TM-142
P1805 1805 BRAKE SW/CIRCUIT — 2 — EC-455
P2100 2100 ETC MOT PWR-B1 — 2×EC-458
P2101 2101 ETC FNCTN/CIRC-B1 — 1 ×EC-460
P2103 2103 ETC MOT PWR — 1 ×EC-458
P 2 11 8 2 11 8 E T C M O T- B 1 — 1 ×EC-464
P 2 11 9 2 11 9 E T C A C T R - B 1 — 1 ×EC-466
P2122 2122 APP SEN 1/CIRC — 1 ×EC-468
P2123 2123 APP SEN 1/CIRC — 1 ×EC-468
P2127 2127 APP SEN 2/CIRC — 1 ×EC-471
P2128 2128 APP SEN 2/CIRC — 1 ×EC-471
P2135 2135 TP SENSOR-B1 — 1 ×EC-475
P2138 2138 APP SENSOR — 1 ×EC-478
P2539 2539 LOW FUEL PRES SEN — 2 ×EC-483
P2541 2541 LOW FUEL PRES SEN — 2 ×EC-483
P2542 2542 LOW FUEL PRES SEN — 2 ×EC-483
P2713 2713 PRESS CONTROL SOL D — 2 ×TM-147
P2722 2722 PRESS CONTROL SOL E — 2 ×TM-148
P2731 2731 PRESS CONTROL SOL F — 2 ×TM-149
P2807 2807 PRESS CONTROL SOL G — 2 ×TM-150
P2A00 2A00 A/F SENSOR1 (B1) — 2 ×EC-487
P2A03 2A03 A/F SENSOR1 (B2) — 2 ×EC-487
DTC*1
Items
(CONSULT-III screen terms) SRT code Trip MIL Reference
page
CONSULT-III
GST*
2ECM*3
Revision: 2010 May2011 QX56

EC-148
< BASIC INSPECTION >[VK56VD]
IDLE AIR VOLUME LEARNING
IDLE AIR VOLUME LEARNING
DescriptionINFOID:0000000006217750
Idle Air Volume Learning is a function of ECM to learn
the idle air volume that keeps engine idle speed within
the specific range. It must be perfo rmed under the following conditions:
 Each time the electric throttle control actuator or ECM is replaced.
 Idle speed or ignition timing is out of the specification.
Work ProcedureINFOID:0000000006217751
1.PRECONDITIONING
Check that all of the following conditions are satisfied.
Learning will be cancelled if any of the follo wing conditions are missed for even a moment.
 Battery voltage: More than 12.9 V (At idle)
 Engine coolant temperature: 70 - 105 °C (158 - 221 °F)
 Selector lever position: P or N
 Electric load switch: OFF
(Air conditioner, headlamp, rear window defogger)
On vehicles equipped with daytime light systems, if the parking brake is applied before the engine is
started the headlamp will not illuminate.
 Steering wheel: Neutral (Straight-ahead position)
 Vehicle speed: Stopped
 Transmission: Warmed-up
- With CONSULT-III: Drive vehicle until “ATF TEMP 2” in “DATA MONITOR” mode of “A/T” system indicates
less than 0.9 V.
- Without CONSULT-III: Drive vehicle for 10 minutes.
Will CONSULT-III be used?
YES >> GO TO 2.
NO >> GO TO 3.
2.PERFORM IDLE AIR VOLUME LEARNING
WITH CONSULT-III
1. Perform Accelerator Pedal Released Position Learning. Refer to EC-146, "
Work Procedure".
2. Perform Throttle Valve Closed Position Learning. EC-147, "
Work Procedure".
3. Start engine and warm it up to normal operating temperature.
4. Select “IDLE AIR VOL LEARN” in “WORK SUPPORT” mode.
5. Touch “START” and wait 20 seconds.
Is
“CMPLT” displayed on CONSULT-III screen?
YES >> GO TO 4.
NO >> GO TO 5.
3.PERFORM IDLE AIR VOLUME LEARNING
WITHOUT CONSULT-III
NOTE:
 It is better to count the ti me accurately with a clock.
 It is impossible to switch the di agnostic mode when an accelerator pedal position sensor circuit has
a malfunction.
1. Perform Accelerator Pedal Released Position Learning. Refer to EC-146, "
Work Procedure".
2. Perform Throttle Valve Closed Position Learning. EC-147, "
Work Procedure".
3. Start engine and warm it up to normal operating temperature.
4. Turn ignition switch OFF and wait at least 10 seconds.
5. Confirm that accelerator pedal is fully releas ed, turn ignition switch ON and wait 3 seconds.
6. Repeat the following procedure quickly 5 times within 5 seconds.
- Fully depress the accelerator pedal.
- Fully release the accelerator pedal.
7. Wait 7 seconds, fully depress the accelerator pedal for approx. 20 seconds until the MIL stops blinking
and turns ON.
8. Fully release the accelerator pedal within 3 seconds after the MIL turns ON.
Revision: 2010 May2011 QX56

P0130, P0150 A/F SENSOR 1EC-229
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
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If “TESTING” is not displayed after 20 seconds, retry from step 2.
CAUTION:
Always drive vehicle at a safe speed.
Is
“TESTING” displayed on CONSULT-III screen?
YES >> GO TO 5.
NO >> Check A/F sensor 1 function again. GO TO 3.
5.PERFORM DTC CONFIRMATION PR OCEDURE FOR MALFUNCTION B-II
Release accelerator pedal fully.
NOTE:
Never apply brake when releasing the accelerator pedal.
Which does
“TESTING” change to?
COMPLETED>>GO TO 6.
OUT OF CONDITION>>Retry DTC CO NFIRMATION PROCEDURE. GO TO 4.
6.PERFORM DTC CONFIRMATION PROCEDURE FOR MALFUNCTION B-III
Touch “SELF-DIAG RESULT”.
Which is displayed on CONSULT-III screen?
YES >> INSPECTION END
NO >> Go to EC-230, "
Diagnosis Procedure".
7.PERFORM COMPONENT FUNCTION CHECK FOR MALFUNCTION B
WITH GST
Perform component function check. Refer to EC-229, "
Component Function Check".
NOTE:
Use component function check to check the overall function of the A/F sensor 1 circuit. During this check, a
1st trip DTC might not be confirmed.
Is the inspection result normal?
YES >> INSPECTION END
NO >> Go to EC-230, "
Diagnosis Procedure".
Component Function CheckINFOID:0000000006217805
1.PERFORM COMPONENT FUNCTION CHECK
WITH GST
1. Start engine and warm it up to normal operating temperature.
2. Drive the vehicle at a speed of 80 km/h (50 MPH) for a few minutes in the suitable gear position.
3. Shift the selector lever position to D, then rel ease the accelerator pedal fully until the vehicle speed
decreases to 50 km/h (31 MPH).
CAUTION:
Always drive vehicle at a safe speed.
NOTE:
Never apply brake when releasing the accelerator pedal.
4. Repeat steps 2 and 3 for 5 times.
5. Stop the vehicle and turn ignition switch OFF.
6. Wait at least 10 seconds and turn ignition switch ON.
7. Turn ignition switch OFF and wait at least 10 seconds.
8. Restart engine.
9. Repeat steps 2 and 3 for 5 times.
10. Stop the vehicle.
11. Check 1st trip DTC.
ENG SPEED 1,750 - 3,200 rpm
VHCL SPEED SE More than 64 km/h (40 mph)
B/FUEL SCHDL 1.0 - 8.0 msec
Selector lever D position
Revision: 2010 May2011 QX56

EC-438
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P1572 ASCD BRAKE SWITCH
P1572 ASCD BRAKE SWITCH
DTC LogicINFOID:0000000006217943
DTC DETECTION LOGIC
NOTE:

If DTC P1572 is displayed with DTC P0605, first pe rform the trouble diagnosis for DTC P0605. Refer
to EC-376, "
DTC Logic".
 This self-diagnosis has the one tr ip detection logic. When malfunction A is detected, DTC is not
stored in ECM memory. And in that case, 1st trip DTC and 1st trip freeze frame data are displayed.
1st trip DTC is erased when ignition switch is tu rned OFF. And even when malfunction A is detected
in two consecutive trips, DTC is not stored in ECM memory.
DTC CONFIRMATION PROCEDURE
1.PRECONDITIONING
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
NOTE:
The procedure for malfunction B is not described. It ta kes an extremely long time to complete the procedure
for malfunction B. By performing the procedure for malfunc tion A, the condition that causes malfunction B can
be detected.
>> GO TO 2.
2.PERFORM DTC CONFIRMATION PROCEDURE FOR MALFUNCTION A
1. Start engine (VDC switch OFF).
2. Press MAIN switch and check that CRUISE indicator is displayed in combination meter.
3. Drive the vehicle for at least 5 consec utive seconds under the following conditions.
CAUTION:
Always drive vehicle at a safe speed.
NOTE:
This procedure may be conducted with the drive wheel s lifted in the shop or by driving the vehicle.
If a road test is expected to be easier , it is unnecessary to lift the vehicle.
4. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Go to EC-439, "Diagnosis Procedure".
NO >> GO TO 3.
3.PERFORM DTC CONFIRMATION PROCEDURE
1. Drive the vehicle for at least 5 consec utive seconds under the following conditions.
CAUTION:
DTC No. Trouble diagnosis name
(Trouble diagnosis content) DTC detecting condition Possible cause
P1572 ASCD BRAKE SW
(ASCD brake switch) A)
When the vehicle speed is above 30 km/h
(19 MPH), ON signals from the stop lamp
switch and the ASCD brake switch are
sent to the ECM at the same time.  Harness or connectors
(The stop lamp switch circuit is shorted.)
 Harness or connectors
(The ASCD brake switch circuit is short-
ed.)
 Stop lamp switch
 ASCD brake switch
 Incorrect stop lamp switch installation
 Incorrect ASCD brake switch installation
ECM
B)
ASCD brake switch signal is not sent to
ECM for extremely long time while the ve-
hicle is being driven.
Vehicle speed More than 30 km/h (19 mph)
Selector lever Suitable position
Revision: 2010 May2011 QX56

P1572 ASCD BRAKE SWITCHEC-439
< DTC/CIRCUIT DIAGNOSIS > [VK56VD]
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Always drive vehicle at a safe speed.
NOTE:
This procedure may be conducted with the drive wheel
s lifted in the shop or by driving the vehicle.
If a road test is expected to be easier , it is unnecessary to lift the vehicle.
2. Check 1st trip DTC.
Is 1st trip DTC detected?
YES >> Go to EC-439, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006217944
1.CHECK OVERALL FUNCTION-I
WITH CONSULT-III
1. Turn ignition switch ON.
2. Select “BRAKE SW1” in “DATA MONITOR” mode with CONSULT-III.
3. Check “BRAKE SW1” indication under the following conditions.
WITHOUT CONSULT-III
1. Turn ignition switch ON.
2. Check the voltage between ECM harness connector terminals as per the following.
Is the inspection result normal?
YES >> GO TO 2.
NO >> GO TO 3.
2.CHECK OVERALL FUNCTION-II
WITH CONSULT-III
Select “BRAKE SW2” and check indication under the following conditions.
WITHOUT CONSULT-III
Check the voltage between ECM harness connector terminals under the following conditions.
Vehicle speed More than 30 km/h (19 mph)
Selector lever Suitable position
Driving location Depress the brake pedal for more than 5 seconds so as
not to come off from the above-mentioned vehicle speed.
Monitor item Condition Indication
BRAKE SW1
(ASCD brake switch) Brake pedalSlightly depressed OFF
Fully released ON
ECM Condition Voltage (V)
Connector +–
Terminal Terminal
E80 147
(ASCD brake switch signal) 175 Brake pedalSlightly depressed Approx. 0
Fully released Battery voltage
Monitor item Condition Indication
BRAKE SW2
(Stop lamp switch) Brake pedalSlightly depressed ON
Fully released OFF
Revision: 2010 May2011 QX56

EC-440
< DTC/CIRCUIT DIAGNOSIS >[VK56VD]
P1572 ASCD BRAKE SWITCH
Is the inspection result normal?
YES >> GO TO 13.
NO >> GO TO 8.
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 the voltage between ASCD brake switch harness connector and ground.
Is the inspection result normal?
YES >> GO TO 5.
NO >> GO TO 4.
4.DETECT MALFUNCTIONING PART
Check the following.
 10 A fuse (No. 3)
 Harness for open or short between ASCD brake switch and fuse
 Loose or poor connection for each connector and harness
>> Repair open circuit or short to ground 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 the continuity between ASCD brake s witch harness connector and ECM harness connector.
4. Also check harness for short to ground and short to power.
Is the inspection result normal?
YES >> GO TO 7.
NO >> GO TO 6.
6.DETECT MALFUNCTIONING PART
Check the following.
 Harness for open or short between ECM and ASCD brake switch
 Loose or poor connection for each connector and harness
>> Repair open circuit, short to ground or short to power in harness or connectors.
7.CHECK ASCD BRAKE SWITCH
Refer to EC-442, "
Component Inspection (ASCD Brake Switch)"
Is the inspection result normal?
ECM
Condition Voltage (V)
Connector +–
Terminal Terminal
E80 158
(Stop lamp switch signal) 175 Brake pedalSlightly depressed Battery voltage
Fully released Approx. 0
ASCD brake switch
Ground Voltage
Connector Terminal
E109 1 Ground Battery voltage
ASCD brake switch ECM Continuity
Connector Terminal Connector Terminal
E109 2 E80 147 Existed
Revision: 2010 May2011 QX56