2011 INFINITI QX56 heater

COMPONENT PARTSEC-21
< SYSTEM DESCRIPTION > [VK56VD]
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Accelerator Pedal
Position SensorINFOID:0000000006217658
The accelerator pedal position (APP) sensor is installed on the
accelerator pedal assembly. The sensor detects the accelerator
position and sends a signal to the ECM.
Accelerator pedal position sensor has two sensors. These sensors
are a kind of potentiometer which transform the accelerator pedal
position into output voltage, and emit the voltage signals to the ECM.
The ECM judges the current opening angle of the accelerator pedal
from these signals and controls the throttle control motor based on
these signals.
Idle position of the accelerator pedal is determined by the ECM
receiving the signal from the accelerator pedal position sensor. The
ECM uses this signal for engine operations such as fuel cut.
Air Fuel Ratio (A/F) Sensor 1INFOID:0000000006217659
DESCRIPTION
The sensor element of the A/F sensor 1 is composed an electrode layer, which transports ions. It has a heater
in the element.
The sensor is capable of precise measurement = 1, but also in the lean and rich range. Together with its
control electronics, the sens or outputs a clear, continuous signal throughout a wide range.
The exhaust gas components diffuse through the diffusion layer at the sensor cell. An electrode layer is
applied voltage, and this current relative oxygen density in lean. Also this current relative hydrocarbon density
in rich.
Therefore, the A/F sensor 1 is able to indicate air fuel ratio by this
electrode layer of current. In addition, a heater is integrated in the
sensor to ensure the required operating temperature of approxi-
mately 760 °C (1,400 °F).
A/F SENSOR 1 HEATER
A/F sensor 1 heater is integrated in the sensor.
The ECM performs ON/OFF duty control of the A/F sensor 1 heater corresponding to the engine operating
condition to keep the temperature of A/F s ensor 1 element within the specified range.
ASCD Brake Switch & Stop Lamp Switch INFOID:0000000006217660
Stop lamp switch and ASCD brake switch are installed to brake pedal bracket.
When the brake pedal is depressed, ASCD brake switch is turned OFF and stop lamp switch is turned ON.
ECM detects the state of the brake pedal by those two types of input (ON/OFF signal).
ASCD Steering SwitchINFOID:0000000006217661
ASCD steering switch has variant values of electrical resistance for each button. ECM reads voltage variation
of switch, and determines which button is operated.
ASCD IndicatorsINFOID:0000000006217662
ASCD operation status is indicated by CRUISE indicator in combination meter.
ECM transmits the ASCD status signal to the combi nation meter via CAN communication according to ASCD
operation.
PBIB1741E
JSBIA0527GB
Revision: 2010 May2011 QX56

EC-28
< SYSTEM DESCRIPTION >[VK56VD]
COMPONENT PARTS
The heated oxygen sensor 2, after three way catalyst (manifold),
monitors the oxygen level in the exhaust gas on each bank.
Even if switching characteristics of
the air fuel ratio (A/F) sensor 1
are shifted, the air fuel ratio is c ontrolled to stoichiometric, by the sig-
nal from the heated oxygen sensor 2.
This sensor is made of ceramic zirconia. The zirconia generates volt-
age from approximately 1 V in richer conditions to 0 V in leaner con-
ditions.
Under normal conditions the heated ox ygen sensor 2 is not used for
engine control operation.
HEATED OXYGEN SENSOR 2 HEATER
Heated oxygen sensor 2 heater is integrated in the sensor.
The ECM performs ON/OFF control of the heated oxy gen sensor 2 heater corresponding to the engine speed,
amount of intake air and engine coolant temperature.
High Pressure Fuel PumpINFOID:0000000006217678
The high pressure fuel pump is installed at the front of the engine bank 2 side and activated by the camshaft.
ECM controls the high pressure fuel pump control sol enoid valve built into the high pressure fuel pump and
adjusts the amount of discharge by changing the suction timing of the low pressure fuel.
Operating Description
SEF327R
Engine speed Heated oxygen sensor 2 heater
Above 3,600 rpm OFF
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 ON
JSBIA0285GB
Revision: 2010 May2011 QX56

DIAGNOSIS SYSTEM (ECM)EC-67
< SYSTEM DESCRIPTION > [VK56VD]
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OLOAD SIGNAL ON/OFF
 Indicates [ON/OFF] condition from the electrical
load signal.
ON: Rear window defogger switch is ON and/or
lighting switch is in 2nd position.
OFF: Both rear window defogger switch and light-
ing switch are OFF.
IGNITION SW ON/OFF  Indicates [ON/OFF] condition from ignition switch
signal.
HEATER FAN SW ON/OFF  Indicates [ON/OFF] condition from the blower fan
ON signal.
BRAKE SW ON/OFF  Indicates [ON/OFF] condition from the stop lamp
switch signal.
IGN TIMING BTDC  Indicates the ignition timing computed by ECM ac-
cording to the input signals.  When the engine is stopped,
a certain value is indicated.
COMBUSTION —  These items are displayed but are not applicable to
this model.
CAL/LD VALUE %  “Calculated load value” indicates the value of the
current air flow divided by peak air flow.
MASS AIRFLOW g/s  Indicates the mass air flow computed by ECM ac-
cording to the signal voltage of the mass air flow
sensor.
PURG VOL C/V %  Indicates the EVAP canister purge volume control
solenoid valve control value computed by the ECM
according to the input signals.
 The opening becomes larger as the value increas-
es.
INT/V SOL (B1)
% The control value of the intake valve timing control
solenoid valve (determined by ECM according to
the input signals) is indicated.
 The advance angle becomes larger as the value increases.
INT/V SOL (B2)
AIR COND RLY ON/OFF
 The air conditioner relay control condition (deter-
mined by ECM according to the input signals) is in-
dicated.
VENT CONT/V ON/OFF  The control condition of the EVAP canister vent
control valve (determined by ECM according to the
input signals) is indicated.
ON: Closed
OFF: Open
THRTL RELAY ON/OFF  Indicates the throttle co
ntrol motor relay control
condition determined by the ECM according to the
input signals.
A/F S1 HTR (B1)
% Air fuel ratio (A/F) sensor 1 heater control value
computed by ECM according to the input signals.
 The current flow to the heater becomes larger as the value increases.
A/F S1 HTR (B2)
HO2S2 HTR (B1)
ON/OFF Indicates [ON/OFF] condition of heated oxygen
sensor 2 heater determined by ECM according to
the input signals.
HO2S2 HTR (B2)
ALT DUTY SIG ON/OFF  The control condition of the power generation volt-
age variable control (determined by ECM accord-
ing to the input signals) is indicated.
ON: Power generation voltage variable control is
active.
OFF: Power generation voltage variable control is
inactive.
I/P PULLY SPD rpm  Indicates the engine speed computed from the in-
put speed sensor signal.
Monitored item Unit Description Remarks
Revision: 2010 May2011 QX56

ECM
EC-73
< ECU DIAGNOSIS INFORMATION > [VK56VD]
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TP SEN 1-B1
 Ignition switch: ON
(Engine stopped)
 Selector lever: D position Accelerator pedal: Fully released More than 0.36 V
Accelerator pedal: Fully depressed Less than 4.75 V
TP SEN 2-B1*
1 Ignition switch: ON (Engine stopped)
 Selector lever: D position Accelerator pedal: Fully released More than 0.36 V
Accelerator pedal: Fully depressed Less than 4.75 V
FUEL T/TMP SE  Ignition switch: ON Indicates fuel tank tempera-
ture
EVAP SYS PRES  Ignition switch: ON Approx. 1.8 - 4.8 V
FUEL LEVEL SE  Ignition switch: ON Depending on fuel level of
fuel tank
START SIGNAL  Ignition switch: ON → START → ON OFF → ON → OFF
CLSD THL POS  Ignition switch: ON
(Engine stopped) Accelerator pedal: Fully released ON
Accelerator pedal: Slightly depressed OFF
AIR COND SIG  Engine: After warming up, idle
the engine Air conditioner switch: OFF OFF
Air conditioner switch: ON
(Compressor operates.)
ON
PW/ST SIGNAL  Engine: After warming up, idle
the engine Steering wheel: Not being turned OFF
Steering wheel: Being turned ON
LOAD SIGNAL  Ignition switch: ON Rear window defogger switch: ON
and/or
Lighting switch: 2nd position
ON
Rear window defogger switch and lighting
switch: OFF OFF
IGNITION SW  Ignition switch: ON → OFF → ON ON → OFF → ON
HEATER FAN SW  Engine: After warming up, idle
the engine Heater fan switch: ON ON
Heater fan switch: OFF OFF
BRAKE SW  Ignition switch: ON Brake pedal: Fully released OFF
Brake pedal: Slightly depressed ON
IGN TIMING  Engine: After warming up
 Selector lever: P or N position
 A/C switch: OFF
No load Idle 1 - 4
°BTDC
2,000 rpm 25 - 45 °BTDC
COMBUSTION — These items are displayed
but are not applicable to this
model.
CAL/LD VALUE  Engine: After warming up
 Selector lever: P or N position
 A/C switch: OFF
No load Idle 5 - 35%
2,500 rpm 5 - 35%
MASS AIRFLOW  Engine: After warming up
 Selector lever: P or N position
 A/C switch: OFF
No load Idle 2.0 - 6.0 g/s
2,500 rpm 7.0 - 20.0 g/s
PURG VOL C/V  Engine: After warming up
 Selector lever: P or N position
 A/C switch: OFF
No load Idle
(Accelerator pedal: Not depressed even
slightly, after engine starting.)
0%
2,000 rpm 5%
INT/V SOL (B1)  Engine: After warming up
 Selector lever: P or N position
 A/C switch: OFF
No load Idle 0 - 2%
2,000 rpm Approx. 0 - 50%
Monitor Item Condition Values/Status
Revision: 2010 May2011 QX56

EC-82
< ECU DIAGNOSIS INFORMATION >[VK56VD]
ECM
37
(V) 175
(B) Cooling fan speed Input [Ignition switch: ON]
 Engine stopped
5 V
[Engine is running]
 Idle speed
 After warm-up condition BATTERY VOLTAGE
(11 - 14 V)
[Engine is running]
 Idle speed
 Before warm-up condition BATTERY VOLTAGE
(11 - 14 V)
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(P/B) 45
(L/O) Power steering pressure sensor Input [Engine is running]
 Steering wheel: Being turned
0.5 - 4.5 V
[Engine is running]
 Steering wheel: Not being turned 0.4 - 0.8 V
40
(W/L) —Sensor ground
(Fuel rail pressure sensor/En-
gine coolant temperature sen-
sor/Engine oil temperature
sensor) —— —
42
(L/Y) 40
(W/L) Engine oil temperature sensor Input [Engine is running] 0 - 4.8 V
Output voltage varies with engine
oil temperature.
45
(L/O) —Sensor ground
(Power steering pressure sen-
sor/ Low fuel pressure sensor/
Electrically-controlled cooling
fan coupling) —— —
46
(SB) 175
(B) Fuel injector driver power supply Input [Ignition switch: ON]
BATTERY VOLTAGE
(11 - 14 V)
[Ignition switch: OFF] 1.5 V
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(G) 175
(B) Heated oxygen sensor 2 heater
(bank 1)
Input[Engine is running]
 Engine speed: Below 3,600 rpm af-
ter 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 10 V
[Ignition switch: ON]
 Engine: Stopped
[Engine is running]
 Engine speed: Above 3,600 rpm BATTERY VOLTAGE
(11 - 14 V)
Te r m i n a l N o .
(Wire color) Description
ConditionVa l u e
(Approx.)
+ – Signal name Input/
Output
JPBIA3332ZZ
JPBIA3733ZZ
JMBIA0037GB
Revision: 2010 May2011 QX56

ECM
EC-83
< ECU DIAGNOSIS INFORMATION > [VK56VD]
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(L/W) 175
(B) A/F sensor 1 heater (bank 1) Input [Engine is running]
 Warm-up condition
 Idle speed
(More than 140 seconds after start-
ing engine) 2.9 - 8.8 V
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(LG/
B) 175
(B) Intake valve timing control sole-
noid valve (bank 1)
Output[Engine is running]
 Warm-up condition
 Idle speed
BATTERY VOLTAGE
(11 - 14 V)
[Engine is running]
 Warm-up condition
 Engine speed: 2,000rpm 7 - 12 V
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(R) 175
(B) Fuel injector driver power supply Output [Engine is running]
 Warm-up condition
 Idle speed
BATTERY VOLTAGE
(11 - 14 V)
[Ignition switch: OFF] 1.5 V
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(L/R) 175
(B) Heated oxygen sensor 2 heater
(bank 2)
Output[Engine is running]
 Engine speed: Below 3,600 rpm af-
ter 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 10 V
[Ignition switch: ON]
 Engine: Stopped
[Engine is running]
 Engine speed: Above 3,600 rpm BATTERY VOLTAGE
(11 - 14 V)
53
(SB) 175
(B) A/F sensor 1 heater (bank 2) Output [Engine is running]
 Warm-up condition
 Idle speed
(More than 140 seconds after start-
ing engine) 2.9 - 8.8 V
Te r m i n a l N o .
(Wire color) Description
ConditionVa l u e
(Approx.)
+ – Signal name Input/
Output
JPBIA3361ZZ
JMBIA0038GB
JMBIA0037GB
JPBIA3361ZZ
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

EC-106
< ECU DIAGNOSIS INFORMATION >[VK56VD]
ECM
EGR
SYSTEM31H EGR function P0400 80H 96H
Low Flow Faults: EGR temp change
rate (short term)
P0400 81H 96H Low Flow Faults: EGR temp change
rate (long term)
P0400 82H 96H Low Flow Faults: Difference between
max EGR temp and EGR temp under
idling condition
P0400 83H 96H Low Flow Faults: Max EGR temp
P1402 84H 96H High Flow Faults: EGR temp increase
rate
VVT
SYSTEM 35H VVT Monitor (Bank1)
P0011 80H 9DH
VTC intake function diagnosis (VTC
alignment check diagnosis)
P0014 81H 9DH VTC exhaust function diagnosis (VTC
alignment check diagnosis)
P0011 82H 9DH VTC intake function diagnosis (VTC
drive failure diagnosis)
P0014 83H 9DH VTC exhaust function diagnosis (VTC
drive failure diagnosis)
36H VVT Monitor (Bank2) P0021 80H 9DH
VTC intake function diagnosis (VTC
alignment check diagnosis)
P0024 81H 9DH VTC exhaust function diagnosis (VTC
alignment check diagnosis)
P0021 82H 9DH VTC intake function diagnosis (VTC
drive failure diagnosis)
P0024 83H 9DH VTC exhaust function diagnosis (VTC
drive failure diagnosis)
EVAP
SYSTEM 39H
EVAP control system leak
(Cap Off) P0455 80H 0CH
Difference in pressure sensor output
voltage before and after pull down
3BH EVAP control system leak
(Small leak) P0442 80H 05H
Leak area index (for more than 0.04
inch)
3CH EVAP control system leak
(Very small leak) P0456 80H 05H
Leak area index (for more than 0.02
inch)
P0456 81H FDH Maximum internal pressure of EVAP
system during monitoring
3DH Purge flow system P0441 83H 0CH Difference in pressure sensor output
voltage before and after vent control
valve close
O2 SEN-
SOR
HEATER 41H
A/F sensor 1 heater
(Bank 1) Low Input:P0031
High Input:P0032 81H 0BHConverted value of Heater electric cur-
rent to voltage
42H Heated oxygen sensor 2 heat-
er (Bank 1) Low Input:P0037
High Input:P0038 80H 0CH
Converted value of Heater electric cur-
rent to voltage
43H Heated oxygen sensor 3 heat-
er (Bank 1) P0043 80H 0CHConverted value of Heater electric cur-
rent to voltage
45H A/F sensor 1 heater
(Bank 2) Low Input:P0051
High Input:P0052
81H 0BHConverted value of Heater electric cur-
rent to voltage
46H Heated oxygen sensor 2 heat-
er (Bank 2) Low Input:P0057
High Input:P0058 80H 0CH
Converted value of Heater electric cur-
rent to voltage
47H Heated oxygen sensor 3 heat-
er (Bank 2) P0063 80H 0CHConverted value of Heater electric cur-
rent to voltage
Item
OBD-
MID Self-diagnostic test item DTC Test value and Test
limit
(GST display) Description
TID Unit and
Scaling ID
Revision: 2010 May2011 QX56