2008 INFINITI QX56 Fuel

ECM
EC-433
< ECU DIAGNOSIS > [VK56DE]
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40
41
42
63
Y/G
P
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G Fuel injector No. 6
Fuel injector No. 4
Fuel injector No. 2
Fuel injector No. 8 [Engine is running]
•
Warm-up condition
• Idle speed
NOTE:
The pulse cycle changes depending on rpm at
idle BATTERY VOLTAGE
(11 - 14V)
[Engine is running]
• Warm-up condition
• Engine speed: 2,000 rpm BATTERY VOLTAGE
(11 - 14V)
45 L/Y EVAP canister purge volume
control solenoid valve [Engine is running]
• Idle speed
• Accelerator pedal: Not depressed even
slightly, after engine starting BATTERY VOLTAGE
(11 - 14V)
[Engine is running]
• Engine speed: About 2,000 rpm (More than 100 seconds after starting engine) BATTERY VOLTAGE
(11 - 14V)
47 Y Sensor power supply
(Throttle position sensor) [Ignition switch: ON]
Approximately 5V
48 SB Sensor power supply
(EVAP control system pres-
sure sensor) [Ignition switch: ON]
Approximately 5V
49 R/Y Sensor power supply
(Refrigerant pressure sensor) [Ignition switch: ON]
Approximately 5V
50 B Throttle position sensor 1 [Ignition switch: ON]
• Engine: Stopped
• Selector lever: D
• Accelerator pedal: Fully released
More than 0.36V
[Ignition switch: ON]
• Engine: Stopped
• Selector lever: D
• Accelerator pedal: Fully depressed Less than 4.75V
TER-
MI-
NAL NO. WIRE
COLOR ITEM
CONDITION DATA (DC Voltage)SEC984C
SEC985C
SEC990C
SEC991C
Revision: March 2010 2008 QX56

ECM
EC-437
< ECU DIAGNOSIS > [VK56DE]
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99 G/R
ASCD steering switch
(Models with ASCD system) [Ignition switch: ON]
• ASCD steering switch: OFF
Approximately 4V
[Ignition switch: ON]
• MAIN switch: Pressed Approximately 0V
[Ignition switch: ON]
• CANCEL switch: Pressed Approximately 1V
[Ignition switch: ON]
• RESUME/ACCELERATE switch: Pressed Approximately 3V
[Ignition switch: ON]
• SET/COAST switch: Pressed Approximately 2V
101 R/W Stop lamp switch [Ignition switch: OFF]
• Brake pedal: Fully released
Approximately 0V
[Ignition switch: OFF]
• Brake pedal: Slightly depressed BATTERY VOLTAGE
(11 - 14V)
102 GR/R PNP signal [Ignition switch: ON]
• Selector lever: P or N
Approximately 0V
[Ignition switch: ON]
• Except the above gear position BATTERY VOLTAGE
(11 - 14V)
104 O Throttle cont rol motor relay[Ignition switch: OFF]
BATTERY VOLTAGE
(11 - 14V)
[Ignition switch: ON] 0 - 1.0V
106 BR/W Accelerator pedal position
sensor 1 [Ignition switch: ON]
• Engine: Stopped
• Accelerator pedal: Fully released
0.5 - 1.0V
[Ignition switch: ON]
• Engine: Stopped
• Accelerator pedal: Fully depressed 4.2 - 4.8V
107 V/R Fuel tank temperature sensor [Engine is running]Approximately 0 - 4.8V
Output voltage varies with fuel
tank temperature.
108 BR/W ICC brake switch
(Models with ICC system)
ASCD brake switch
(Models with ASCD system) [Ignition switch: ON]
• Brake pedal: Slightly depressed
Approximately 0V
[Ignition switch: ON]
• Brake pedal: Fully released BATTERY VOLTAGE
(11 - 14V)
109 L/W Ignition switch [Ignition switch: OFF]
0V
[Ignition switch: ON] BATTERY VOLTAGE
(11 - 14V)
111 W / B ECM relay
(Self shut-off) [Engine is running]
[Ignition switch: OFF]
• For a few seconds after turning ignition
switch OFF 0 - 1.5V
[Ignition switch: OFF]
• More than a few seconds after turning igni- tion switch OFF BATTERY VOLTAGE
(11 - 14V)
11 3 G R F u e l p u m p r e l a y [Ignition switch: ON]
• For 1 second after turning ignition switch
ON
[Engine is running] 0 - 1.5V
[Ignition switch: ON]
• More than 1 second after turning ignition switch ON BATTERY VOLTAGE
(11 - 14V)
TER-
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NAL NO. WIRE
COLOR ITEM
CO
NDITION DA

TA (DC Voltage)
Revision: March 2010 2008 QX56

EC-460
< ECU DIAGNOSIS >[VK56DE]
ECM
• 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 pa rt of ECM related diagnoses are continuously detected
as NG for 5 trips, ECM warns the driver that engi ne control system malfunctions and MIL circuit is open by
means of operating fail-safe function.
The fail-safe function also operates when above diagnos es 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
P0103 Mass air flow sensor circuit Engine speed will not rise more than 2,400 rpm due to the fuel cut.
P0117
P0118 Engine coolant tempera-
ture sensor circuit Engine coolant temperature will be determined by ECM based on the following condition.
CONSULT-IIl displays the engine coolant temperature decided by ECM.
Condition Engine coolant temperature decided
(CONSULT-IIl display)
Just as ignition switch is turned ON
or START 40
°C (104 °F)
Approx 4 minutes or more after en-
gine starting. 80
°C (176 °F)
Except as shown above 40 - 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
P2135 Throttle 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
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.
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 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
P2138 Accelerator pedal 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.
Engine operating condition in fail-safe mode
Engine speed will not rise more than 2,500 rpm due to the fuel cut
Revision: March 2010 2008 QX56

ECM
EC-461
< ECU DIAGNOSIS > [VK56DE]
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DTC Inspection Priority ChartINFOID:0000000001351338
If some DTCs are displayed at the same time, perform inspections one by one based on the following priority
chart.
NOTE:
•
If DTC U1000 and/or U1001 is displayed with other DTC, first perform the trouble diagnosis for DTC
U1000, U1001. Refer to EC-87
.
• If DTC U1010 is displayed with ot her DTC, first perform the trouble diagnosis for DTC U1010. Refer to
EC-88
.
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
• P0116 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 posi tion sensor (PHASE)
• P0460 P0461 P0462 P0463 Fuel level sensor
• P0500 Vehicle speed sensor
• P0605 ECM
• P0643 Sensor power supply
• P0700 TCM
• P0705 Transmission range 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
Revision: March 2010 2008 QX56

EC-462
< ECU DIAGNOSIS >[VK56DE]
ECM
DTC Index
INFOID:0000000001351328
EMISSION-RELATED DIAGNOSTIC INFORMATION ITEMS
× :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 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 P0731 P0732 P0733 P0734 P0735 P0740 P0744 P0745 P1730 P1752 P1757 P1762 P1767
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 sys tem (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
Priority
Detected items (DTC)
Items
(CONSULT-IIl screen terms) DTC*
1
SRT code Trip
MILReference
page
CONSULT-IIl
GST*
2ECM*3
CAN COMM CIRCUIT U1000
1000*5—1 ×EC-87
CAN COMM CIRCUIT U1001
1001*5—1 or 2*9
2*10—
EC-87
CONTROL UNIT(CAN) U10101010—1×EC-88
NO DTC IS DETECTED.
FURTHER TESTING
MAY BE REQUIRED. P0000
0000——
Flashing*7EC-55
INT/V TIM CONT-B1 P00110011—2×EC-40
INT/V TIM CONT-B2 P00210021—2×EC-40
A/F SEN1 HTR (B1) P00310031—2×EC-97
A/F SEN1 HTR (B1) P00320032—2×EC-97
HO2S2 HTR (B1) P00370037—2×EC-100
HO2S2 HTR (B1) P00380038—2×EC-100
A/F SEN1 HTR (B2) P00510051—2×EC-97
Revision: March 2010 2008 QX56

ECM
EC-463
< ECU DIAGNOSIS > [VK56DE]
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OA/F SEN1 HTR (B2)
P00520052—2×EC-97
HO2S2 HTR (B2) P00570057—2×EC-100
HO2S2 HTR (B2) P00580058—2×EC-100
INT/V TIM V/CIR-B1 P00750075—2×EC-103
INT/V TIM V/CIR-B2 P00810081—2×EC-103
MAF SEN/CIRCUIT-B1 P01010101—2×EC-106
MAF SEN/CIRCUIT-B1 P01020102—1×EC-113
MAF SEN/CIRCUIT-B1 P01030103—1×EC-113
IAT SEN/CIRCUIT-B1 P01120112—2×EC-118
IAT SEN/CIRCUIT-B1 P01130113—2×EC-118
ECT SEN/CIRC P01160116—2×EC-121
ECT SEN/CIRC P01170117—1×EC-124
ECT SEN/CIRC P01180118—1×EC-124
TP SEN 2/CIRC-B1 P01220122—1×EC-128
TP SEN 2/CIRC-B1 P01230123—1×EC-128
ECT SENSOR P01250125—2×EC-132
IAT SENSOR-B1 P01270127—2×EC-135
THERMSTAT FNCTN P01280128—2×EC-138
A/F SENSOR1 (B1) P01300130—2×EC-141
A/F SENSOR1 (B1) P01310131—2×EC-145
A/F SENSOR1 (B1) P01320132—2×EC-149
A/F SENSOR1 (B1) P01330133 ×2 ×EC-153
HO2S2 (B1) P01370137 ×2 ×EC-159
HO2S2 (B1) P01380138 ×2 ×EC-164
HO2S2 (B1) P01390139 ×2 ×EC-171
A/F SENSOR1 (B2) P01500150—2×EC-141
A/F SENSOR1 (B2) P01510151—2×EC-145
A/F SENSOR1 (B2) P01520152—2×EC-149
A/F SENSOR1 (B2) P01530153 ×2 ×EC-153
HO2S2 (B2) P01570157 ×2 ×EC-159
HO2S2 (B2) P01580158 ×2 ×EC-164
HO2S2 (B2) P01590159 ×2 ×EC-171
FUEL SYS-LEAN-B1 P01710171—2×EC-176
FUEL SYS-RICH-B1 P01720172—2×EC-182
FUEL SYS-LEAN-B2 P01740174—2×EC-176
FUEL SYS-RICH-B2 P01750175—2×EC-182
FTT SENSOR P01810181—2×EC-188
FTT SEN/CIRCUIT P01820182—2×EC-191
FTT SEN/CIRCUIT P01830183—2×EC-191
TP SEN 1/CIRC-B1 P02220222—1×EC-194
TP SEN 1/CIRC-B1 P02230223—1×EC-194
MULTI CYL MISFIRE P03000300—2×EC-198
Items
(CONSULT-IIl screen terms) DTC*
1
SRT code Trip
MILReference
page
CONSULT-IIl
GST*
2ECM*3
Revision: March 2010 2008 QX56

EC-464
< ECU DIAGNOSIS >[VK56DE]
ECM
CYL 1 MISFIRE
P03010301—2×EC-198
CYL 2 MISFIRE P03020302—2×EC-198
CYL 3 MISFIRE P03030303—2×EC-198
CYL 4 MISFIRE P03040304—2×EC-198
CYL 5 MISFIRE P03050305—2×EC-198
CYL 6 MISFIRE P03060306—2×EC-198
CYL 7 MISFIRE P03070307—2×EC-198
CYL 8 MISFIRE P03080308—2×EC-198
KNOCK SEN/CIRC-B1 P03270327—2—EC-204
KNOCK SEN/CIRC-B1 P03280328—2—EC-204
KNOCK SEN/CIRC-B2 P03320332—2—EC-204
KNOCK SEN/CIRC-B2 P03330333—2—EC-204
CKP SEN/CIRCUIT P03350335—2×EC-207
CMP SEN/CIRC-B1 P03400340—2×EC-211
TW CATALYST SYS-B1 P04200420 ×2 ×EC-215
TW CATALYST SYS-B2 P04300430 ×2 ×EC-215
EVAP PURG FLOW /MON P0441 0441 ×2 ×EC-219
EVAP SMALL LEAK P04420442 ×2 ×EC-224
PURG VOLUME CONT/V P04430443—2×EC-231
PURG VOLUME CONT/V P04440444—2×EC-236
PURG VOLUME CONT/V P04450445—2×EC-236
VENT CONTROL VALVE P04470447—2×EC-239
VENT CONTROL VALVE P04480448—2×EC-243
EVAP SYS PRES SEN P04510451—2×EC-247
EVAP SYS PRES SEN P04520452—2×EC-250
EVAP SYS PRES SEN P04530453—2×EC-254
EVAP GROSS LEAK P04550455—2×EC-259
EVAP VERY SML LEAK P04560456
×*42 ×EC-266
FUEL LEV SEN SLOSH P04600460—2×EC-274
FUEL LEVEL SENSOR P04610461—2×EC-276
FUEL LEVL SEN/CIRC P04620462—2×EC-278
FUEL LEVL SEN/CIRC P04630463—2×EC-278
VEH SPEED SEN/CIRC*6P0500 0500—2×EC-280
ISC SYSTEM P05060506—2×EC-282
ISC SYSTEM P05070507—2×EC-284
PW ST P SEN/CIRC P05500550—2—EC-286
ECM BACK UP/CIRC P06030603—2×EC-289
ECM P06050605—1 or 2 × or — EC-291
SENSOR POWER/CIRC P06430643—1×EC-293
TRANSMISSION CONT P07000700—1×TM-42
T/M RANGE SENSOR A P07050705—2×TM-43
ATF TEMP SEN/CIRC P07100710—2×TM-71
Items
(CONSULT-IIl screen terms) DTC*
1
SRT code Trip
MILReference
page
CONSULT-IIl
GST*
2ECM*3
Revision: March 2010 2008 QX56

ECM
EC-467
< ECU DIAGNOSIS > [VK56DE]
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Procedures for clearing the DTC and the 1st trip DT
C from the ECM memory are described in "HOW TO
ERASE EMISSION-RELATED DIAGNOSTIC INFORMATION".
For malfunctions in which 1st trip DTCs are displa yed, refer to "EMISSION-RELATED DIAGNOSTIC INFOR-
MATION ITEMS". These items are required by legal r egulations to continuously monitor the system/compo-
nent. In addition, the items monitored non-cont inuously are also displayed on CONSULT-III.
1st trip DTC is specified in Service $07 of SAE J1979. 1st trip DTC detection occurs without lighting up the MIL
and therefore does not warn the driver of a malfunction. However, 1st trip DTC detection will not prevent the
vehicle from being tested, for example during Inspection/Maintenance (I/M) tests.
When a 1st trip DTC is detected, check, print out or write down and erase (1st trip) DTC and Freeze Frame
data as specified in Work Flow procedure Step 2, refer to EC-8, "
Trouble Diagnosis Introduction". Then per-
form DTC Confirmation Procedure or Overall Function Che ck to try to duplicate the malfunction. If the mal-
function is duplicated, the item requires repair.
How to Read DTC and 1st Trip DTC
DTC and 1st trip DTC can be read by the following methods.
With CONSULT-III
With GST
CONSULT-III or GST (Generic Scan Tool ) Examples: P0340, P0850, P1148, etc.
These DTCs are prescribed by SAE J2012.
(CONSULT-III also displays the malfunctioning component or system.)
No Tools
The number of blinks of the MIL in the Diagnostic Test Mode II (Self-Diagnostic Results) indicates the DTC.
Example: 0340, 0850, 1148, etc.
These DTCs are controlled by NISSAN.
• 1st trip DTC No. is the same as DTC No.
• Output of a DTC indicates a malfunc tion. However, GST or the Diagnostic Test Mode II do not indi-
cate whether the malfunction is stil l occurring or has occurred in the past and has returned to nor-
mal. CONSULT-III can identify malfunction status as shown below. Therefore, using CONSULT-III (if
available) is recommended.
DTC or 1st trip DTC of a malfunction is display ed in SELF-DIAGNOSTIC RESULTS mode of CONSULT-III.
Time data indicates how many times the vehicle was driven after the last detection of a DTC.
If the DTC is being detected currently, the time data will be [0].
If a 1st trip DTC is stored in the ECM, the time data will be [1t].
FREEZE FRAME DATA AND 1ST TRIP FREEZE FRAME DATA
The ECM records the driving conditions such as fuel system status, calculated load value, engine coolant tem-
perature, short term fuel trim, long term fuel trim, engi ne speed, vehicle speed, absolute throttle position, base
fuel schedule and intake air temperature at the moment a malfunction is detected.
Data which are stored in the ECM memory, along with the 1st trip DTC, are called 1st trip freeze frame data.
The data, stored together with the DTC data, are ca lled freeze frame data and displayed on CONSULT-III or
GST. The 1st trip freeze frame dat a can only be displayed on the CONSULT-III screen, not on the GST. For
details, see EC-63, "
CONSULT-III Function (ENGINE)".
Only one set of freeze frame data (either 1st trip freez e frame data or freeze frame data) can be stored in the
ECM. 1st trip freeze frame data is stored in the ECM me mory along with the 1st trip DTC. There is no priority
for 1st trip freeze frame data and it is updated each time a different 1st trip DTC is detected. However, once
freeze frame data (2nd trip detection/MIL on) is stored in the ECM memory, 1st trip freeze frame data is no
longer stored. Remember, only one set of freeze frame data can be stored in the ECM. The ECM has the fol-
lowing priorities to update the data.
For example, the EGR malfunction (Priority: 2) was detected and the fr eeze frame data was stored in the 2nd
trip. After that when the misfire (Priority: 1) is detected in another trip, the freeze frame data will be updated
from the EGR malfunction to the misfire. The 1st trip freeze frame data is updated each time a different mal-
function is detected. There is no priority for 1st tr ip freeze frame data. However, once freeze frame data is
stored in the ECM memory, 1st trip freeze data is no longer stored (because only one freeze frame data or 1st
trip freeze frame data can be stored in the ECM). If freeze frame data is stored in the ECM memory and freeze
Priority Items
1 Freeze frame data Misfire — DTC: P0300 - P0308
Fuel Injection System Function — DTC: P0171, P0172, P0174, P0175
2 Except the above items (Includes A/T related items)
3 1st trip freeze frame data
Revision: March 2010 2008 QX56