2007 INFINITI QX56 sensor

EC-88
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
Fail-Safe Chart
INFOID:0000000003531619
When the DTC listed below is detected, the ECM enters fail-safe mode and the MIL lights up.
Priority Detected items (DTC)
1 • U1000 U1001 CAN communication line
• U1010 CAN communication
• P0101 P0102 P0103 Mass air flow sensor
• P0112 P0113 P0127 Intake air temperature sensor
• P0117 P0118 P0125 Engine coolant temperature sensor
• P0122 P0123 P0222 P0223 P1225 P1226 P2135 Throttle position sensor
• P0128 Thermostat function
• P0181 P0182 P0183 Fuel tank temperature sensor
• P0327 P0328 P0332 P0333 Knock sensor
• P0335 Crankshaft position sensor (POS)
• P0340 Camshaft position sensor (PHASE)
• P0460 P0461 P0462 P0463 Fuel level sensor
• P0500 Vehicle speed sensor
• P0605 ECM
• P0643 Sensor power supply
• P0700 TCM
• P0705 Park/neutral position (PNP) switch
• P0850 Park/neutral position (PNP) switch
• P1550 P1551 P1552 P1553 P1554 Battery current sensor
• P1610 - P1615 NATS
• P2122 P2123 P2127 P2128 P2138 Accelerator pedal position sensor
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 P0153 P2A00 P2A03 Air fuel ratio (A/F) sensor 1
• P0137 P0138 P0139 P0157 P0158 P0159 Heated oxygen sensor 2
• 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 P0740 P0744 P0745 P1730 P1752 P1754 P1757 P1759 P1762 P1764 P1767 P1769 P1772
P1774 A/T related sensors, solenoid valves and switches
• P1217 Engine over temperature (OVERHEAT)
• P1140 P1145 Intake valve timing control position sensor
• P1805 Brake switch
• P2100 P2103 P2118 Electric throttle control actuator
• P2101 Electric throttle control function
3 • P0011 P0021 Intake valve timing control
• P0171 P0172 P0174 P0175 Fuel injection system function
• P0300 - P0308 Misfire
• P0420 P0430 Three way catalyst function
• P0442 EVAP control system (SMALL LEAK)
• P0455 EVAP control system (GROSS LEAK)
• P0456 EVAP control system (VERY SMALL LEAK)
• P0506 P0507 Idle speed control system
• P1148 P1168 Closed loop control
• P1211 TCS control unit
• P1212 TCS communication line
• P1421 Cold start control
• P1564 ICC/ASCD steering switch
• P1568 ICC command value
• P1572 ICC/ASCD brake switch
• P1574 ICC/ASCD vehicle speed sensor
• P2119 Electric throttle control actuator

TROUBLE DIAGNOSIS
EC-89
< SERVICE INFORMATION >
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• When there is an open circuit on MIL circuit, the ECM cannot warn the driver by lighting up MIL when there
is malfunction on engine control system.
Therefore, when electrical controlled throttle and part of ECM related diagnoses are continuously detected
as NG for 5 trips, ECM warns the driver that engine control system malfunctions and MIL circuit is open by
means of operating fail-safe function.
The fail-safe function also operates when above diagnoses except MIL circuit are detected and demands the
driver to repair the malfunction.
DTC No. Detected items Engine operating condition in fail-safe mode
P0102
P0103Mass air flow sensor circuit Engine speed will not rise more than 2,400 rpm due to the fuel cut.
P0117
P0118Engine coolant tempera-
ture sensor circuitEngine coolant temperature will be determined by ECM based on the time after turning
ignition switch ON or START.
CONSULT-II displays the engine coolant temperature decided by ECM.
ConditionEngine coolant temperature decided
(CONSULT-II display)
Just as ignition switch is turned ON
or START40°C (104°F)
More than approx. 4 minutes after
ignition ON or START80°C (176°F)
Except as shown above40 - 80°C (104 - 176°F)
(Depends on the time)
When the fail-safe system for engine coolant temperature sensor is activated, the cooling
fan operates while engine is running.
P0122
P0123
P0222
P0223
P2135Throttle position sensor The ECM controls the electric throttle control actuator in regulating the throttle opening in
order for the idle position to be within +10 degrees.
The ECM regulates the opening speed of the throttle valve to be slower than the normal
condition.
So, the acceleration will be poor.
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.
P2100
P2103Throttle 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.
P2101 Electric throttle control
functionECM 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 by regulating the throttle opening to 20
degrees or less.
(When ECM detects the throttle valve is stuck open:)
While the vehicle is driving, it slows down gradually by fuel cut. After the vehicle stops, the
engine stalls.
The engine can restart in N or P position, and engine speed will not exceed 1,000 rpm or
more.
P2122
P2123
P2127
P2128
P2138Accelerator pedal position
sensorThe ECM controls the electric throttle control actuator in regulating the throttle opening in
order for the idle position to be within +10 degrees.
The ECM regulates the opening speed of the throttle valve to be slower than the normal
condition.
So, the acceleration will be poor.
Engine operating condition in fail-safe mode Engine speed will not rise more than 2,500 rpm due to the fuel cut

EC-90
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
Symptom Matrix Chart
INFOID:0000000003531620
SYSTEM — BASIC ENGINE CONTROL SYSTEM
SYMPTOM
Refer-
ence page
HARD/NO START/RESTART (EXCP. HA)
ENGINE STALL
HESITATION/SURGING/FLAT SPOT
SPARK KNOCK/DETONATION
LACK OF POWER/POOR ACCELERATION
HIGH IDLE/LOW IDLE
ROUGH IDLE/HUNTING
IDLING VIBRATION
SLOW/NO RETURN TO IDLE
OVERHEATS/WATER TEMPERATURE HIGH
EXCESSIVE FUEL CONSUMPTION
EXCESSIVE OIL CONSUMPTION
BATTERY DEAD (UNDER CHARGE)
Warranty symptom code AA AB AC AD AE AF AG AH AJ AK AL AM HA
Fuel Fuel pump circuit 11232 22 3 2EC-613
Fuel pressure regulator system 334444444 4EC-80
Injector circuit 11232 22 2EC-608
Evaporative emission system 334444444 4EC-33
Air Positive crankcase ventilation sys-
tem
334444444 41EC-45
Incorrect idle speed adjustment 1 1 1 1 1EC-71
Electric throttle control actuator 112332222 2 2EC-543
,
EC-548
,
EC-554
,
EC-559
IgnitionIncorrect ignition timing adjustment 33111 11 1EC-71
Ignition circuit 11222 22 2EC-626
Main power supply and ground circuit 22333 33 23EC-139
Mass air flow sensor circuit
1
122
222 2EC-186,
EC-194
Engine coolant temperature sensor circuit
333EC-205,
EC-217
Air fuel ratio (A/F) sensor 1 circuitEC-225
,
EC-234
,
EC-242
,
EC-250
,
EC-588

Throttle position sensor circuit
22EC-210
,
EC-318
,
EC-477
,
EC-479
,
EC-574
Accelerator pedal position sensor circuit 3 2 1EC-440
,
EC-561
,
EC-567
,
EC-581
Knock sensor circuit 2 3EC-332
Crankshaft position sensor (POS) circuit 2 2EC-336

TROUBLE DIAGNOSIS
EC-91
< SERVICE INFORMATION >
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1 - 6: The numbers refer to the order of inspection.
(continued on next page)
SYSTEM — ENGINE MECHANICAL & OTHER
Camshaft position sensor (PHASE) circuit 3 2EC-342
Vehicle speed signal circuit 2 3 3 3EC-429
Power steering pressure sensor circuit 2 3 3EC-435
ECM 22333333333EC-440,
EC-444
Intake valve timing control solenoid valve cir-
cuit32 13223 3EC-178
Park/Neutral position (PNP) switch circuit 3 3 3 3 3EC-452
Refrigerant pressure sensor circuit 2 3 3 4EC-638
Electrical load signal circuit 3EC-606
Air conditioner circuit 223333333 3 2AT C - 3 0
ABS actuator and electric unit (control unit) 4EC-467
,
EC-468

or BRC-11
SYMPTOM
Refer-
ence page
HARD/NO START/RESTART (EXCP. HA)
ENGINE STALL
HESITATION/SURGING/FLAT SPOT
SPARK KNOCK/DETONATION
LACK OF POWER/POOR ACCELERATION
HIGH IDLE/LOW IDLE
ROUGH IDLE/HUNTING
IDLING VIBRATION
SLOW/NO RETURN TO IDLE
OVERHEATS/WATER TEMPERATURE HIGH
EXCESSIVE FUEL CONSUMPTION
EXCESSIVE OIL CONSUMPTION
BATTERY DEAD (UNDER CHARGE)
Warranty symptom code AA AB AC AD AE AF AG AH AJ AK AL AM HA

EC-92
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
SYMPTOM
Reference
page
HARD/NO START/RESTART (EXCP. HA)
ENGINE STALL
HESITATION/SURGING/FLAT SPOT
SPARK KNOCK/DETONATION
LACK OF POWER/POOR ACCELERATION
HIGH IDLE/LOW IDLE
ROUGH IDLE/HUNTING
IDLING VIBRATION
SLOW/NO RETURN TO IDLE
OVERHEATS/WATER TEMPERATURE HIGH
EXCESSIVE FUEL CONSUMPTION
EXCESSIVE OIL CONSUMPTION
BATTERY DEAD (UNDER CHARGE)
Warranty symptom code AA AB AC AD AE AF AG AH AJ AK AL AM HA
Fuel Fuel tank
5
5FL-10
Fuel piping 5 5 5 5 5 5FL-4
Va p o r l o c k—
Valve deposit
5 555 55 5—
Poor fuel (Heavy weight gasoline,
Low octane)—
Air Air duct
55555 5EM-15
Air cleanerEM-15
Air leakage from air duct
(Mass air flow sensor — electric
throttle control actuator)
5555EM-15
Electric throttle control actuatorEM-17
Air leakage from intake manifold/
Collector/GasketEM-17
Cranking Battery
111111
11SC-4
Generator circuitSC-15
Starter circuit 3SC-9
Signal plate 6EM-38
Park/Neutral position (PNP)
switch4AT- 9 9
Engine Cylinder head
55555 55 5EM-64
Cylinder head gasket 4 3
Cylinder block
66666 66 64
EM-78
Piston
Piston ring
Connecting rod
Bearing
Crankshaft
Va l v e
mecha-
nismTiming chain
55555 55 5EM-38
CamshaftEM-46
Intake valve timing controlEM-46
Intake valve
3EM-64
Exhaust valve

EC-94
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
Engine Control Component Parts Location
INFOID:0000000003531621
1. ECM 2. Battery current sensor 3. Power steering pressure sensor
4. Ignition coil (with power transistor)
and spark plug (bank 2)5. Refrigerant pressure sensor 6. Intake valve timing control position
sensor (bank 2)
7. Intake valve timing control solenoid
valve (bank 2)8. Engine coolant temperature sensor 9. Electric throttle control actuator
10. Intake valve timing control position
sensor (bank 1)11. Intake valve timing control solenoid
valve (bank 1)12. Cooling fan motor
13. Camshaft position sensor (PHASE) 14. Ignition coil (with power transistor)
and spark plug (bank 1)15. Mass air flow sensor (with intake air
temperature sensor)
16. A/F sensor 1 (bank 1) 17. EVAP service port 18. Fuel injector (bank 1)
19. Knock sensor (bank 1) 20. EVAP canister purge volume control
solenoid valve21. Knock sensor (bank 2)
22. Fuel injector (bank 2) 23. A/F sensor 1 (bank 2) 24. IPDM E/R
BBIA0743E

TROUBLE DIAGNOSIS
EC-95
< SERVICE INFORMATION >
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1. Body ground (view with battery re-
moved)2. Body ground (view with battery re-
moved)3. Body ground
4. No. 1 ignition coil 5. Engine ground 6. Mass air flow sensor (with intake air
temperature sensor)
7. IPDM E/R 8. Battery 9. Radiator hose
10. Camshaft position sensor (PHASE) 11. Electric throttle control actuator
(view with intake air duct removed)12. Cooling fan motor harness connec-
tor
BBIA0778E

EC-96
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
1. EVAP canister purge volume control
solenoid valve (view with engine
cover removed)2. EVAP service port (view with engine
cover removed)3. Crankshaft position sensor (POS)
(view from under the vehicle)
4. Engine oil pan (view from under the
vehicle)5. Condenser-1 6. Brake fluid reservoir
7. EVAP canister (view with fuel tank
removed)8. EVAP control system pressure sen-
sor (view with fuel tank removed)9. EVAP canister vent control valve
(view with fuel tank removed)
10. Rear suspension member (view with
fuel tank removed)11. Refrigerant pressure sensor (view
with hood open)12. Intake valve timing control position
sensor (bank 2) (view with engine
cover and intake air duct removed)
BBIA0783E