engine INFINITI QX56 2009 Factory Service Manual

ECM
EC-425
< ECU DIAGNOSIS > [VK56DE]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
21
22
23
44
O/L
BR
GR/W
O Fuel injector No. 5
Fuel injector No. 3
Fuel injector No. 1
Fuel injector No. 7 [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)
24
43 GR/G
GR/G
A/F sensor 1 heater (bank 2) [Engine is running]

Warm-up condition
 Idle speed
(More than 140 seconds after starting en-
gine) Approximately 2.9 - 8.8V
25 O/G Heated oxygen sensor 2 heat-
er (bank 2) [Engine is running]
 Engine speed: Below 3,600 rpm after the
following conditions are met.
- Engine: After warming up
- Keeping the engine speed between 3,500
and 4,000 rpm for 1 minute and at idle for 1
minute under no load 0 - 1.0V
[Ignition switch: ON]
 Engine: Stopped
[Engine is running]
 Engine speed: Above 3,600 rpm BATTERY VOLTAGE
(11 - 14V)
32 L EVAP control system pres-
sure sensor
[Ignition switch: ON]
Approximately 1.8 - 4.8V
34 R/B Intake air temperature sensor [Engine is running]Approximately 0 - 4.8V
Output voltage varies with intake
air temperature.
35 BR/R A/F sensor 1 (bank 1) [Engine is running]

Warm-up condition
 Engine speed: 2,000 rpm Approximately 1.8V
Output voltage varies with air fuel
ratio.
36 W Knock sensor (bank 2) [Engine is running]
 Idle speedApproximately 2.5V
TER-
MI-
NAL NO. WIRE
COLOR ITEM CONDITION DATA (DC Voltage)SEC984C
SEC985C
PBIA8148J
Revision: December 20092009 QX56

EC-426
< ECU DIAGNOSIS >[VK56DE]
ECM
40
41
42
63Y/G
P
L
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: December 20092009 QX56

ECM
EC-427
< ECU DIAGNOSIS > [VK56DE]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
51 W Mass air flow sensor
[Engine is running]

Warm-up condition
 Idle speed 1.0 - 1.3V
[Engine is running]
 Warm-up condition
 Engine speed: 2,500 rpm 1.7 - 2.1V
53 L Intake valve timing control po-
sition sensor (Bank 2) [Engine is running]

Warm-up condition
 Idle speed 0 - 1.0V
[Engine is running]
 Engine speed: 2,000 rpm 0 - 1.0V
55 R Heated oxygen sensor 2
(bank 1) [Engine is running]
 Revving engine from idle to 3,000 rpm
quickly after the following conditions are
met.
- Engine: After warming up
- Keeping the engine speed between 3,500 and 4,000 rpm for 1 minute and at idle for 1
minute under no load 0 - Approximately 1.0V
56 BR/G A/F sensor 1 (bank 1) [Ignition switch: ON]Approximately 2.2V
46
60
61
62 L/R
GR/R
O/W
Y/R Ignition signal No. 7
Ignition signal No. 5
Ignition signal No. 3
Ignition signal No. 1 [Engine is running]

Warm-up condition
 Idle speed
NOTE:
The pulse cycle changes depending on rpm at
idle 0 - 0.3V
[Engine is running]
 Warm-up condition
 Engine speed: 2,500 rpm 0.1 - 0.6V
66 R Sensor ground
(Throttle position sensor) [Engine is running]

Warm-up condition
 Idle speed Approximately 0V
67 B Sensor ground [Engine is running]

Warm-up condition
 Idle speed Approximately 0V
68 W/L Sensor power supply
(PSP sensor) [Ignition switch: ON]
Approximately 5V
TER-
MI-
NAL NO. WIRE
COLOR ITEM CONDITION DATA (DC Voltage)
PBIB2046E
SEC986C
SEC987C
Revision: December 20092009 QX56

EC-428
< ECU DIAGNOSIS >[VK56DE]
ECM
69 W Throttle position sensor 2[Ignition switch: ON]
 Engine: Stopped
 Selector lever: D
 Accelerator pedal: Fully released
Less than 4.75V
[Ignition switch: ON]
 Engine: Stopped
 Selector lever: D
 Accelerator pedal: Fully depressed More than 0.36V
70 B/W Refrigerant pressure sensor [Engine is running]

Warm-up condition
 Both A/C switch and blower fan switch: ON (Compressor operates.) 1.0 - 4.0V
71 R Battery current sensor [Engine is running]
 Battery: Fully charged*
 Idle speedApproximately 2.6 - 3.5V
72 Y Intake valve timing control po-
sition sensor (Bank 1) [Engine is running]

Warm-up condition
 Idle speed 0 - 1.0V
[Engine is running]
 Engine speed: 2,000rpm 0 - 1.0V
73 Y/B Engine coolant temperature
sensor [Engine is running] Approximately 0 - 4.8V
Output voltage varies with engine
coolant temperature.
74 L Heated oxygen sensor 2
(bank 2) [Engine is running]
 Revving engine from idle to 3,000 rpm
quickly after the following conditions are
met.
- Engine: After warming up
- Keeping the engine speed between 3,500
and 4,000 rpm for 1 minute and at idle for 1
minute under no load 0 - Approximately 1.0V
75 L/P A/F sensor 1 (bank 2) [Ignition switch: ON]Approximately 2.2V
78 B/W Sensor ground
(Heated oxygen sensor 2) [Engine is running]

Warm-up condition
 Idle speed Approximately 0V
TER-
MI-
NAL NO. WIRE
COLOR ITEM CONDITION DATA (DC Voltage)
PBIB2046E
Revision: December 20092009 QX56

ECM
EC-429
< ECU DIAGNOSIS > [VK56DE]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
65
79
80
81
G/R
V/W
W/R
W/G Ignition signal No. 8
Ignition signal No. 6
Ignition signal No. 4
Ignition signal No. 2 [Engine is running]

Warm-up condition
 Idle speed
NOTE:
The pulse cycle changes depending on rpm at
idle 0 - 0.3V
[Engine is running]
 Warm-up condition
 Engine speed: 2,500 rpm 0.1 - 0.6V
82 B/R Sensor ground
(APP sensor 1) [Engine is running]

Warm-up condition
 Idle speed Approximately 0V
83 G/W Sensor ground
(APP sensor 2) [Engine is running]

Warm-up condition
 Idle speed Approximately 0V
86 P CAN communication line — —
90 L Sensor power supply
(APP sensor 1) [Ignition switch: ON]
Approximately 5V
91 W/R Sensor power supply
(APP sensor 2) [Ignition switch: ON]
Approximately 5V
94 L CAN communication line — —
98 G/R Accelerator pedal position
sensor 2 [Ignition switch: ON]
 Engine: Stopped
 Accelerator pedal: Fully released
0.25 - 0.50V
[Ignition switch: ON]
 Engine: Stopped
 Accelerator pedal: Fully depressed 2.0 - 2.5V
99 G/R ASCD steering switch
(Models with ICC system) [Ignition switch: ON]
 ICC steering switch: OFF
Approximately 4.3V
[Ignition switch: ON]
 MAIN switch: Pressed Approximately 0V
[Ignition switch: ON]
 CANCEL switch: Pressed Approximately 1.3V
[Ignition switch: ON]
 RESUME/ACCELERATE switch: Pressed Approximately 3.7V
[Ignition switch: ON]
 SET/COAST switch: Pressed Approximately 3V
[Ignition switch: ON]
 DISTANCE switch: Pressed Approximately 2.2V
TER-
MI-
NAL NO. WIRE
COLOR ITEM CONDITION DATA (DC Voltage)SEC986C
SEC987C
Revision: December 20092009 QX56

EC-430
< ECU DIAGNOSIS >[VK56DE]
ECM
99 G/RASCD 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 Transmission range 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)
113 GR Fuel pump relay [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-
MI-
NAL NO.
WIRE
COLOR ITEM CONDITION DATA (DC Voltage)
Revision: December 20092009 QX56

ECM
EC-431
< ECU DIAGNOSIS > [VK56DE]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
: Average voltage for pulse signal (Actual pulse signal can be confirmed by oscilloscope.)
*:Before measuring the terminal voltage, confir m that the battery is fully charged. Refer to PG-77
.
11 5
11 6
B
B/W
ECM ground [Engine is running]
 Idle speed Body ground
11 7 L / Y EVAP canister vent control
valve
[Ignition switch: ON] BATTERY VOLTAGE
(11 - 14V)
11 9
120 BR
BR
Power supply for ECM
[Ignition switch: ON] BATTERY VOLTAGE
(11 - 14V)
121 W Power supply for ECM
(Back-up) [Ignition switch: OFF] BATTERY VOLTAGE
(11 - 14V)
TER-
MI-
NAL NO. WIRE
COLOR ITEM CONDITION DATA (DC Voltage)
Revision: December 20092009 QX56

EC-432
< ECU DIAGNOSIS >[VK56DE]
ECM
Wiring Diagram - ENGINE CONTROL SYSTEM -
INFOID:0000000003771734
AABWA0099GB
Revision: December 20092009 QX56

EC-454
< ECU DIAGNOSIS >[VK56DE]
ECM
 When there is an open circuit on MIL circuit, the ECM c
annot 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 thro ttle 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: December 20092009 QX56

ECM
EC-455
< ECU DIAGNOSIS > [VK56DE]
C
D
E
F
G H
I
J
K L
M A
EC
NP
O
DTC Inspection Priority ChartINFOID:0000000003771736
If some DTCs are displayed at the same time, per
form 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-86
.
 If DTC P0607 is displayed with ot her DTC, first perform the trouble diagnosis for DTC P0607. Refer to
EC-284
.
Priority Detected items (DTC)
1  U1000 U1001 CAN communication line  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 P0607 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: December 20092009 QX56