2004 INFINITI QX56 brake sensor

ENGINE CONTROL SYSTEM
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Revision: August 20072004 QX56
System ChartUBS00GZD
*1: This sensor is not used to control the engine system. This is used only for the on board diagnosis.
*2: This sensor is not used to control the engine system under normal conditions.
*3: This input signal is sent to the ECM through CAN communication line.
*4: This output signal is sent from the ECM through CAN communication line.Input (Sensor) ECM Function Output (Actuator)

Camshaft position sensor (PHASE)

Crankshaft position sensor (POS)

Mass air flow sensor

Engine coolant temperature sensor

A/F sensor 1

Throttle position sensor

Accelerator pedal position sensor

Park/neutral position (PNP) switch

Intake air temperature sensor

Power steering pressure sensor

Ignition switch

Battery voltage

Knock sensor

Refrigerant pressure sensor

Stop lamp switch

ASCD steering switch

ASCD brake switch

Fuel level sensor*1 *3

EVAP control system pressure sensor

Fuel tank temperature sensor*1

Heated oxygen sensor 2*2

TCM (Transmission control module)*3

ABS actuator and electric unit (control unit)*3

Air conditioner switch*3

Wheel sensor*3

Electrical load signal*3
Fuel injection & mixture ratio control Fuel injector
Electronic ignition system Power transistor
Nissan torque demand control system

Electric throttle control actuator

Fuel injector
Fuel pump control Fuel pump relay
ASCD vehicle speed control Electric throttle control actuator
On board diagnostic system
MIL (On the instrument panel)*
4
A/F sensor 1 heater control A/F sensor 1 heater
Heated oxygen sensor 2 heater control Heated oxygen sensor 2 heater
EVAP canister purge flow controlEVAP canister purge volume control
solenoid valve
Air conditioning cut control
Air conditioner relay*
4
Cooling fan control
Cooling fan relay*4
ON BOARD DIAGNOSIS for EVAP system EVAP canister vent control valve

EC-40Revision: August 2007
BASIC SERVICE PROCEDURE
2004 QX56
19. CHECK AIR FUEL RATIO (A/F) SENSOR 1 FUNCTION
With CONSULT-II
1. Turn ignition switch OFF and wait at a least 10 seconds.
2. Start engine and warm it up to normal operating temperature.
3. Drive the vehicle at a speed of 80 km/h (50 MPH) for a few minutes in D position with “OD” OFF.
NOTE:
Keep the accelerator pedal as steady as possible during the cruising.
4. Set “OD” ON, then release the accelerator pedal fully until the vehicle speed decreases to 50 km/h (30
MPH).
NOTE:
Never apply brake during releasing the accelerator pedal.
5. Repeat steps 3 to 4 five times.
6. Stop the vehicle and connect CONSULT-II to the vehicle.
7. Make sure that no (1st trip) DTC is displayed in “SELF-DIAG RESULTS” mode.
OK or NG
OK >>INSPECTION END
NG >> GO TO 21.
20. CHECK AIR FUEL RATIO (A/F) SENSOR 1 FUNCTION
With GST
1. Turn ignition switch OFF and wait at a least 10 seconds.
2. Start engine and warm it up to normal operating temperature.
3. Drive the vehicle at a speed of 80 km/h (50 MPH) for a few minutes in D position with “OD” OFF.
NOTE:
Keep the accelerator pedal as steady as possible during the cruising.
4. Set “OD” ON, then release the accelerator pedal fully until the vehicle speed decreases to 50 km/h (30
MPH).
NOTE:
Never apply brake during releasing the accelerator pedal.
5. Repeat steps 3 to 4 five times.
6. Stop the vehicle and connect GST to the vehicle.
7. Make sure that no (1st trip) DTC is displayed.
OK or NG
OK >>INSPECTION END
NG >> GO TO 21.

BASIC SERVICE PROCEDURE
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Revision: August 20072004 QX56
29. CHECK AIR FUEL RATIO (A/F) SENSOR 1 FUNCTION
With CONSULT-II
1. Turn ignition switch OFF and wait at a least 10 seconds.
2. Start engine and warm it up to normal operating temperature.
3. Drive the vehicle at a speed of 80 km/h (50 MPH) for a few minutes in D position with “OD” OFF.
NOTE:
Keep the accelerator pedal as steady as possible during the cruising.
4. Set “OD” ON, then release the accelerator pedal fully until the vehicle speed decreases to 50 km/h (30
MPH).
NOTE:
Never apply brake during releasing the accelerator pedal.
5. Repeat steps 3 to 4 five times.
6. Stop the vehicle and connect CONSULT-II to the vehicle.
7. Make sure that no (1st trip) DTC is displayed in “SELF-DIAG RESULTS” mode.
OK or NG
OK >> GO TO 4.
NG >> GO TO 31.
30. CHECK AIR FUEL RATIO (A/F) SENSOR 1 FUNCTION
With GST
1. Turn ignition switch OFF and wait at a least 10 seconds.
2. Start engine and warm it up to normal operating temperature.
3. Drive the vehicle at a speed of 80 km/h (50 MPH) for a few minutes in D position with “OD” OFF.
NOTE:
Keep the accelerator pedal as steady as possible during the cruising.
4. Set “OD” ON, then release the accelerator pedal fully until the vehicle speed decreases to 50 km/h (30
MPH).
NOTE:
Never apply brake during releasing the accelerator pedal.
5. Repeat steps 3 to 4 five times.
6. Stop the vehicle and connect GST to the vehicle.
7. Make sure that no (1st trip) DTC is displayed.
OK or NG
OK >> GO TO 4.
NG >> GO TO 31.
31. DETECT MALFUNCTIONING PART
Check the following.

Check fuel pressure regulator, and repair or replace if necessary. Refer to EC-47, "FUEL PRESSURE
CHECK" .

Check mass air flow sensor and its circuit, and repair or replace if necessary. Refer to EC-146 and EC-
154 .

Check injector and its circuit, and repair or replace if necessary. Refer to EC-595 .

Check engine coolant temperature sensor and its circuit, and repair or replace if necessary. Refer to EC-
165 and EC-178 .
OK or NG
OK >> GO TO 33.
NG >> 1. Repair or replace.
2. GO TO 32.

BASIC SERVICE PROCEDURE
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Revision: August 20072004 QX56
On vehicles equipped with daytime light systems, if the parking brake is applied before the engine
is started, the headlamp will not be illuminated.

Steering wheel: Neutral (Straight-ahead position)

Vehicle speed: Stopped

Transmission: Warmed-up
For models with CONSULT-II, drive vehicle until “FLUID TEMP SE” in “DATA MONITOR” mode of “A/T”
system indicates less than 0.9V.
For models without CONSULT-II, drive vehicle for 10 minutes.
OPERATION PROCEDURE
With CONSULT-II
1. Perform EC-44, "Accelerator Pedal Released Position Learning" .
2. Perform EC-44, "
Throttle Valve Closed Position Learning" .
3. Start engine and warm it up to normal operating temperature.
4. Check that all items listed under the topic PREPARATION (previously mentioned) are in good order.
5. Select “IDLE AIR VOL LEARN” in “WORK SUPPORT” mode.
6. Touch “START” and wait 20 seconds.
7. Make sure that “CMPLT” is displayed on CONSULT-II screen. If
“CMPLT” is not displayed, Idle Air Volume Learning will not be
carried out successfully. In this case, find the cause of the inci-
dent by referring to the Diagnostic Procedure below.
8. Rev up the engine two or three times and make sure that idle
speed and ignition timing are within the specifications.
Without CONSULT-II
NOTE:

It is better to count the time accurately with a clock.

It is impossible to switch the diagnostic mode when an accelerator pedal position sensor circuit
has a malfunction.
1. Perform EC-44, "
Accelerator Pedal Released Position Learning" .
SEF 2 17 Z
SEF 4 54 Y
ITEM SPECIFICATION
Idle speed 650±50 rpm (in P or N position)
Ignition timing 15±5° BTDC (in P or N position)
MBIB0238E

EC-52Revision: August 2007
ON BOARD DIAGNOSTIC (OBD) SYSTEM
2004 QX56
A/F SEN1 HTR (B2) P1051 1051×××EC-354
A/F SEN1 HTR (B2) P1052 1052×××EC-354
ECM BACK UP/CIRC P1065 1065 — —×EC-361
ETC ACTR P1121 1121 — — —EC-365
ETC FUNCTION/CIRC P1122 1122 — — —EC-367
E T C M O T P W R P 11 2 4 11 2 4 — — —EC-373
E T C M O T P W R P 11 2 6 11 2 6 — — —EC-373
E T C M O T P 11 2 8 11 2 8 — — —EC-378
HO2S2 (B1) P1146 1146×××EC-383
HO2S2 (B1) P1147 1147×××EC-395
CLOSED LOOP-B1 P1148 1148 — — —EC-407
HO2S2 (B2) P1166 1166×××EC-383
HO2S2 (B2) P1167 1167×××EC-395
CLOSED LOOP-B2 P1168 1168 — — —EC-407
TCS C/U FUNCTN P1211 1211 — —×EC-408
TCS/CIRC P1212 1212 — —×EC-409
ENG OVER TEMP P1217 1217 — — —EC-410
CTP LEARNING P1225 1225 — —×EC-420
CTP LEARNING P1226 1226 — —×EC-422
SENSOR POWER/CIRC P1229 1229 — — —EC-424
A/F SENSOR1 (B1) P1271 1271 — —×EC-429
A/F SENSOR1 (B1) P1272 1272 — —×EC-437
A/F SENSOR1 (B1) P1273 1273 — —×EC-445
A/F SENSOR1 (B1) P1274 1274 — —×EC-454
A/F SENSOR1 (B1) P1276 1276 — —×EC-463
A/F SENSOR1 (B1) P1278 1278×××EC-472
A/F SENSOR1 (B1) P1279 1279×××EC-484
A/F SENSOR1 (B2) P1281 1281 — —×EC-429
A/F SENSOR1 (B2) P1282 1282 — —×EC-437
A/F SENSOR1 (B2) P1283 1283 — —×EC-445
A/F SENSOR1 (B2) P1284 1284 — —× EC-454
A/F SENSOR1 (B2) P1286 1286 — —×EC-463
A/F SENSOR1 (B2) P1288 1288×××EC-472
A/F SENSOR1 (B2) P1289 1289×××EC-484
PURG VOLUME CONT/V P1444 1444 — —×EC-496
VENT CONTROL VALVE P1446 1446 — —×EC-504
ASCD SW P1564 1564 — — —EC-510,
EC-517
ACC COMMAND VALUE*8P1568 1568 — — —EC-524
ASCD BRAKE SW P1572 1572 — — —EC-525,
EC-534
ASCD VHL SPD SEN*7P1574 1574 — — —EC-542,
EC-534
Items
(CONSULT-II screen terms)DTC*
1
SRT codeTest value/
Test limit
(GST only)1st trip DTCReference
page CONSULT-II
GST*
2ECM*3

ON BOARD DIAGNOSTIC (OBD) SYSTEM
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Revision: August 20072004 QX56
*1: 1st trip DTC No. is the same as DTC No.
*2: This number is prescribed by SAE J2012.
*3: In Diagnostic Test Mode II (Self-diagnostic results). This number is controlled by NISSAN.
*4: When the fail-safe operations for both self-diagnoses occur at the same time, the MIL illuminates.
*5: The trouble shooting for this DTC needs CONSULT-II.
*6: SRT code will not be set if the self-diagnostic result is NG.
*7: 2WD models
*8: Models with ICC system
DTC AND 1ST TRIP DTC
The 1st trip DTC (whose number is the same as the DTC number) is displayed for the latest self-diagnostic
result obtained. If the ECM memory was cleared previously, and the 1st trip DTC did not reoccur, the 1st trip
DTC will not be displayed.
If a malfunction is detected during the 1st trip, the 1st trip DTC is stored in the ECM memory. The MIL will not
light up (two trip detection logic). If the same malfunction is not detected in the 2nd trip (meeting the required
driving pattern), the 1st trip DTC is cleared from the ECM memory. If the same malfunction is detected in the
2nd trip, both the 1st trip DTC and DTC are stored in the ECM memory and the MIL lights up. In other words,
the DTC is stored in the ECM memory and the MIL lights up when the same malfunction occurs in two consec-
utive trips. If a 1st trip DTC is stored and a non-diagnostic operation is performed between the 1st and 2nd
trips, only the 1st trip DTC will continue to be stored. For malfunctions that blink or light up the MIL during the
1st trip, the DTC and 1st trip DTC are stored in the ECM memory.
Procedures for clearing the DTC and the 1st trip DTC from the ECM memory are described in EC-62, "
HOW
TO ERASE EMISSION-RELATED DIAGNOSTIC INFORMATION" .
For malfunctions in which 1st trip DTCs are displayed, refer to EC-50, "
EMISSION-RELATED DIAGNOSTIC
INFORMATION ITEMS" . These items are required by legal regulations to continuously monitor the system/
component. In addition, the items monitored non-continuously are also displayed on CONSULT-II.
NATS MALFUNCTIONP1610 -
P16151610 - 1615 — —×BL-138
P-N POS SW/CIRCUIT P1706 1706 — —×EC-546
TURBINE REV S/CIRC P1716 1716 — —×AT- 1 3 4
A/T INTERLOCK P1730 1730 — — —AT- 1 3 9
I/C SOLENOID/CIRC P1752 1752 — — —AT- 1 4 5
I/C SOLENOID FNCTN P1754 1754 — — —AT- 1 4 8
FR/B SOLENOID/CIRC P1757 1757 — — —AT- 1 5 1
FR/B SOLENOID/CIRC P1759 1759 — — —AT- 1 5 4
D/C SOLENOID/CIRC P1762 1762 — — —AT- 1 5 7
D/C SOLENOID FNCTN P1764 1764 — — —AT- 1 6 0
HLR/C SOL/CIRC P1767 1767 — — —AT- 1 6 3
HLR/C SOL FNCTN P1769 1769 — — —AT- 1 6 6
LC/B SOLENOID/CIRC P1772 1772 — — —AT- 1 6 9
LC/B SOLENOID FNCT P1774 1774 — — —AT- 1 7 2
BRAKE SW/CIRCUIT P1805 1805 — —×EC-551
APP SEN 1/CIRC P2122 2122 — — —EC-556
APP SEN 1/CIRC P2123 2123 — — —EC-556
APP SEN 2/CIRC P2127 2127 — — —EC-562
APP SEN 2/CIRC P2128 2128 — — —EC-562
TP SENSOR P2135 2135 — — —EC-569
APP SENSOR P2138 2138 — — —EC-576
Items
(CONSULT-II screen terms)DTC*
1
SRT codeTest value/
Test limit
(GST only)1st trip DTCReference
page CONSULT-II
GST*
2ECM*3

TROUBLE DIAGNOSIS
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Revision: August 20072004 QX56
Fail-safe ChartUBS00GZY
When the DTC listed below is detected, the ECM enters fail-safe mode and the MIL lights up.
2
P0037 P0038 P0057 P0058 Heated oxygen sensor 2 heater

P0138 P0139 P0158 P0159 P1146 P1147 P1166 P1167 Heated oxygen sensor 2

P0441 EVAP control system purge flow monitoring

P0444 P0445 P1444 EVAP canister purge volume control solenoid valve

P0447 P1446 EVAP canister vent control valve

P0451 P0452 P0453 EVAP control system pressure sensor

P0550 Power steering pressure sensor

P0700 P0710 P0720 P0740 P0744 P0745 P1706 P1716 P1730 P1752 P1754 P1757 P1759 P1762 P1764 P1767
P1769 P1772 P1774 A/T related sensors and solenoid valves

P1031 P1032 P1051 P1052 A/F sensor 1 heater

P1065 ECM power supply

P1122 Electric throttle control function

P1124 P1126 P1128 Electric throttle control actuator

P1217 Engine over temperature (OVERHEAT)

P1271 P1272 P1273 P1274 P1276 P1278 P1279 P1281 P1282 P1283 P1284 P1286 P1288 P1289 A/F sensor 1

P1805 Brake switch
3

P0171 P0172 P0174 P0175 Fuel injection system function

P0300 - P0308 Misfire

P0420 P0430 Three way catalyst function

P0442 P0456 EVAP control system (SMALL LEAK, VERY SMALL LEAK)

P0455 EVAP control system (GROSS LEAK)

P0506 P0507 Idle speed control system

P1121 Electric throttle control actuator

P1148 P1168 Closed loop control

P1211 TCS control unit

P1212 TCS communication line

P1564 ICC steering switch/ASCD steering switch

P1568 ICC command value

P1572 ICC brake switch/ASCD brake switch

P1574 ICC vehicle speed sensor/ASCD vehicle speed sensor Priority Detected items (DTC)
DTC No. Detected items Engine operating condition in fail-safe mode
P0101
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.

EC-102Revision: August 2007
TROUBLE DIAGNOSIS
2004 QX56
99 G/YICC steering switch
(models with ICC system)[Ignition switch: ON]

ICC steering switch: OFFApproximately 4.3V
[Ignition switch: ON]

ON/OFF(MAIN) switch: PressedApproximately 0V
[Ignition switch: ON]

CANCEL switch: PressedApproximately 1.3V
[Ignition switch: ON]

DISTANCE switch: PressedApproximately 2.2V
[Ignition switch: ON]

COAST/SET switch: PressedApproximately 3.0V
[Ignition switch: ON]

ACCEL/RESUME switch: PressedApproximately 3.7V
99 G/YASCD steering switch
(models with ASCD system)[Ignition switch: ON]

ASCD steering switch: OFFApproximately 4V
[Ignition switch: ON]

ON/OFF(MAIN) switch: PressedApproximately 0V
[Ignition switch: ON]

CANCEL switch: PressedApproximately 1V
[Ignition switch: ON]

COAST/SET switch: PressedApproximately 2V
[Ignition switch: ON]

ACCEL/RESUME switch: PressedApproximately 3V
101 R/W Stop lamp switch[Ignition switch: OFF]

Brake pedal: Fully releasedApproximately 0V
[Ignition switch: OFF]

Brake pedal: DepressedBATTERY VOLTAGE
(11 - 14V)
102 GR/R PNP switch[Ignition switch: ON]

Shift lever position: P or NApproximately 0V
[Ignition switch: ON]

Except the above gear positionBATTERY VOLTAGE
(11 - 14V)
104 O Throttle control motor relay[Ignition switch: OFF]BATTERY VOLTAGE
(11 - 14V)
[Ignition switch: ON]0 - 1.0V
106 BR/WAccelerator pedal position
sensor 1[Ignition switch: ON]

Engine stopped

Accelerator pedal: Fully released0.5 - 1.0V
[Ignition switch: ON]

Engine stopped

Accelerator pedal: Fully depressed3.9 - 4.7V
107 V/RFuel tank temperature sen-
sor[Engine is running]Approximately 0 - 4.8V
Output voltage varies with fuel
tank temperature.
108 BR/W ASCD brake switch[Ignition switch: ON]

Brake pedal: DepressedApproximately 0V
[Ignition switch: ON]

Brake pedal: Fully releasedBATTERY VOLTAGE
(11 - 14V) TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)