2007 INFINITI QX56 heater

DTC P0037, P0038, P0057, P0058 HO2S2 HEATER
EC-177
< SERVICE INFORMATION >
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1. Check resistance between HO2S2 terminals as follows.
2. If NG, replace heated oxygen sensor 2.
CAUTION:
• Discard any heated oxygen sensor which has been dropped
from a height of more than 0.5 m (19.7 in) onto a hard surface
such as a concrete floor; use a new one.
• Before installing new oxygen sensor, clean exhaust system
threads using Oxygen Sensor Thread Cleaner tool J-43897-18
or J-43897-12 and approved anti-seize lubricant.
Removal and InstallationINFOID:0000000003531671
HEATED OXYGEN SENSOR 2
Refer to EM-21.
Terminal No. Resistance
2 and 3 8 - 10 Ω at 25°C (77°F)
1 and 2, 3, 4
∞ Ω
(Continuity should not exist)
4 and 1, 2, 3
SEF249Y

DTC P0130, P0150 A/F SENSOR 1
EC-225
< SERVICE INFORMATION >
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DTC P0130, P0150 A/F SENSOR 1
Component DescriptionINFOID:0000000003531736
The air fuel ratio (A/F) sensor 1 is a planar one-cell limit current sen-
sor. The sensor element of the A/F sensor 1 is composed an elec-
trode 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 sensor
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 hydrocar-
bon 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 about 800°C
(1,472°F).
CONSULT-II Reference Value in Data Monitor ModeINFOID:0000000003531737
Specification data are reference values.
On Board Diagnosis LogicINFOID:0000000003531738
To judge the malfunction, the diagnosis checks that the A/F signal computed by ECM from the A/F sensor 1
signal fluctuates according to fuel feedback control.
DTC Confirmation ProcedureINFOID:0000000003531739
Perform PROCEDURE FOR MALFUNCTION A first.
If the DTC cannot be confirmed, perform PROCEDURE FOR MALFUNCTION B.
NOTE:
If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 11V at idle.
PROCEDURE FOR MALFUNCTION A
PBIB3353E
PBIB3354E
MONITOR ITEM CONDITION SPECIFICATION
A/F SEN1 (B1)
A/F SEN1 (B2)• Engine: After warming upMaintaining engine speed at
2,000 rpmFluctuates around 2.2V
DTC No. Trouble diagnosis name DTC detecting condition Possible Cause
P0130
0130
(Bank 1)
Air fuel ratio (A/F) sensor 1
circuitA)The A/F signal computed by ECM from the A/F
sensor 1 signal is constantly in the range other
than approx. 2.2V.• Harness or connectors
(The A/F sensor 1 circuit is open
or shorted.)
• Air fuel ratio (A/F) sensor 1 P0150
0150
(Bank 2)B)The A/F signal computed by ECM from the A/F
sensor 1 signal is constantly approx. 2.2V.

DTC P0130, P0150 A/F SENSOR 1
EC-229
< SERVICE INFORMATION >
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Do not use ECM ground terminals when measuring input/output voltage. Doing so may result in dam-
age to the ECM's transistor. Use a ground other than ECM terminals, such as the ground.
: Average voltage for pulse signal (Actual pulse signal can be confirmed by oscilloscope.)TER-
MI-
NAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
2 LG/B A/F sensor 1 heater (bank 1)[Engine is running]
•Warm-up condition
• Idle speed
(More than 140 seconds after starting en-
gine)Approximately 2.9 - 8.8V
35 BR/R A/F sensor 1 (bank 1)[Engine is running]
•Warm-up condition
• Engine speed: 2,000 rpmApproximately 1.8V
Output voltage varies with air fuel
ratio.
56 BR/G A/F sensor 1 (bank 1)[Ignition switch: ON]Approximately 2.2V
PBIA8148J

DTC P0130, P0150 A/F SENSOR 1
EC-231
< SERVICE INFORMATION >
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: Average voltage for pulse signal (Actual pulse signal can be confirmed by oscilloscope.)
Diagnosis ProcedureINFOID:0000000003531742
1.CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten three ground screws on the body.
Refer to EC-143, "
Ground Inspection".
OK or NG
OK >> GO TO 2.
NG >> Repair or replace ground connections.
2.CHECK AIR FUEL RATIO (A/F) SENSOR 1 POWER SUPPLY CIRCUIT
1. Disconnect A/F sensor 1 harness connector.
2. Turn ignition switch ON.
TER-
MI-
NAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
16 G/L A/F sensor 1 (bank 2)[Engine is running]
•Warm-up condition
• Engine speed: 2,000 rpmApproximately 1.8V
Output voltage varies with air fuel
ratio.
24
43GR/G
GR/GA/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
75 L/P A/F sensor 1 (bank 2)[Ignition switch: ON]Approximately 2.2V
PBIA8148J
BBIA0354E
BBIA0376E

EC-234
< SERVICE INFORMATION >
DTC P0131, P0151 A/F SENSOR 1
DTC P0131, P0151 A/F SENSOR 1
Component DescriptionINFOID:0000000003531744
The air fuel ratio (A/F) sensor 1 is a planar one-cell limit current sen-
sor. The sensor element of the A/F sensor 1 is composed an elec-
trode 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 sensor
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 hydrocar-
bon 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 about 800°C
(1,472°F).
CONSULT-II Reference Value in Data Monitor ModeINFOID:0000000003531745
Specification data are reference values.
On Board Diagnosis LogicINFOID:0000000003531746
To judge the malfunction, the diagnosis checks that the A/F signal computed by ECM from the A/F sensor 1
signal is not inordinately low.
DTC Confirmation ProcedureINFOID:0000000003531747
NOTE:
If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 10.5V at idle.
WITH CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Select “A/F SEN1 (B1)” or “A/F SEN1 (B2)” in “DATA MONITOR” mode with CONSULT-II.
PBIB3353E
PBIB3354E
MONITOR ITEM CONDITION SPECIFICATION
A/F SEN1 (B1)
A/F SEN1 (B2)• Engine: After warming upMaintaining engine speed at
2,000 rpmFluctuates around 2.2V
DTC No. Trouble diagnosis name DTC detecting condition Possible Cause
P0131
0131
(Bank 1)
Air fuel ratio (A/F) sensor 1
circuit low voltage• The A/F signal computed by ECM from the A/
F sensor 1 signal is constantly approx. 0V.• Harness or connectors
(The A/F sensor 1 circuit is open or
shorted.)
• Air fuel ratio (A/F) sensor 1 P0151
0151
(Bank 2)

DTC P0131, P0151 A/F SENSOR 1
EC-237
< SERVICE INFORMATION >
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Do not use ECM ground terminals when measuring input/output voltage. Doing so may result in dam-
age to the ECM's transistor. Use a ground other than ECM terminals, such as the ground.
: Average voltage for pulse signal (Actual pulse signal can be confirmed by oscilloscope.)TER-
MI-
NAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
2 LG/B A/F sensor 1 heater (bank 1)[Engine is running]
•Warm-up condition
• Idle speed
(More than 140 seconds after starting en-
gine)Approximately 2.9 - 8.8V
35 BR/R A/F sensor 1 (bank 1)[Engine is running]
•Warm-up condition
• Engine speed: 2,000 rpmApproximately 1.8V
Output voltage varies with air fuel
ratio.
56 BR/G A/F sensor 1 (bank 1)[Ignition switch: ON]Approximately 2.2V
PBIA8148J

DTC P0131, P0151 A/F SENSOR 1
EC-239
< SERVICE INFORMATION >
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: Average voltage for pulse signal (Actual pulse signal can be confirmed by oscilloscope.)
Diagnosis ProcedureINFOID:0000000003531749
1.CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten three ground screws on the body.
Refer to EC-143, "
Ground Inspection".
OK or NG
OK >> GO TO 2.
NG >> Repair or replace ground connections.
2.CHECK AIR FUEL RATIO (A/F) SENSOR 1 POWER SUPPLY CIRCUIT
1. Disconnect A/F sensor 1 harness connector.
2. Turn ignition switch ON.
TER-
MI-
NAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
16 G/L A/F sensor 1 (bank 2)[Engine is running]
•Warm-up condition
• Engine speed: 2,000 rpmApproximately 1.8V
Output voltage varies with air fuel
ratio.
24
43GR/G
GR/GA/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
75 L/P A/F sensor 1 (bank 2)[Ignition switch: ON]Approximately 2.2V
PBIA8148J
BBIA0354E
BBIA0376E

EC-242
< SERVICE INFORMATION >
DTC P0132, P0152 A/F SENSOR 1
DTC P0132, P0152 A/F SENSOR 1
Component DescriptionINFOID:0000000003531751
The air fuel ratio (A/F) sensor 1 is a planar one-cell limit current sen-
sor. The sensor element of the A/F sensor 1 is composed an elec-
trode 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 sensor
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 hydrocar-
bon 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 about 800°C
(1,472°F).
CONSULT-II Reference Value in Data Monitor ModeINFOID:0000000003531752
Specification data are reference values.
On Board Diagnosis LogicINFOID:0000000003531753
To judge the malfunction, the diagnosis checks that the A/F signal computed by ECM from the A/F sensor 1
signal is not inordinately high.
DTC Confirmation ProcedureINFOID:0000000003531754
NOTE:
If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 10.5V at idle.
WITH CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Select “A/F SEN1 (B1)” or “A/F SEN1 (B2)” in “DATA MONITOR” mode with CONSULT-II.
PBIB3353E
PBIB3354E
MONITOR ITEM CONDITION SPECIFICATION
A/F SEN1 (B1)
A/F SEN1 (B2)• Engine: After warming upMaintaining engine speed at
2,000 rpmFluctuates around 2.2V
DTC No. Trouble diagnosis name DTC detecting condition Possible Cause
P0132
0132
(Bank 1)
Air fuel ratio (A/F) sensor 1
circuit high voltage• The A/F signal computed by ECM from the A/F
sensor 1 signal is constantly approx. 5V.• Harness or connectors
(The A/F sensor 1 circuit is open or
shorted.)
• Air fuel ratio (A/F) sensor 1 P0132
0132
(Bank 2)