ESP INFINITI FX35 2007 Service Manual

DTC P0031, P0032, P0051, P0052 A/F SENSOR 1 HEATER EC-837
[VK45DE]
C
D E
F
G H
I
J
K L
M A
EC
Revision: 2006 July 2007 FX35/FX45
DTC P0031, P0032, P0051, P0052 A/F SENSOR 1 HEATERPFP:22693
DescriptionNBS004K7
SYSTEM DESCRIPTION
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 sensor 1 element at the specified range.
CONSULT-II Reference Value in Data Monitor ModeNBS004K8
Specification data are reference values.
On Board Diagnosis LogicNBS004K9
DTC Confirmation ProcedureNBS004KA
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 between 10.5V and 16V at
idle.
WITH CONSULT-II
1. Turn ignition switch ON and select “DATA MONITOR” mode with CONSULT-II.
2. Start engine and let it idle for at least 10 seconds.
3. If 1st trip DTC is detected, go to EC-841, "
Diagnostic Procedure"
.
WITH GST
Follow the procedure “WITH CONSULT-II” above.
Sensor Input Signal to ECM ECM function Actuator
Camshaft position sensor (PHASE)
Crankshaft position sensor (POS) Engine speed
Air fuel ratio (A/F) sensor 1
heater control Air fuel ratio (A/F) sensor 1
heater
Mass air flow sensor Amount of intake air
MONITOR ITEM CONDITION SPECIFICATION
A/F S1 HTR (B1)
A/F S1 HTR (B2)

Engine: After warming up, idle the engine 0 - 100%
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0031
0031
(Bank 1) Air fuel ratio (A/F) sensor
1 heater control circuit
low The current amperage in the A/F sensor 1 heater
circuit is out of the normal range.
(An excessively low voltage signal is sent to ECM
through the A/F sensor 1 heater.)

Harness or connectors
(The A/F sensor 1 heater circuit is
open or shorted.)

A/F sensor 1 heater
P0051
0051
(Bank 2)
P0032
0032
(Bank 1) Air fuel ratio (A/F) sensor
1 heater control circuit
high The current amperage in the A/F sensor 1 heater
circuit is out of the normal range.
(An excessively high voltage signal is sent to ECM
through the A/F sensor 1 heater.)

Harness or connectors
(The A/F sensor 1 heater circuit is
shorted.)

A/F sensor 1 heater
P0052
0052
(Bank 2)
SEF058Y

EC-844
[VK45DE]
DTC P0037, P0038, P0057, P0058 HO2S2 HEATER
Revision: 2006 July 2007 FX35/FX45
DTC P0037, P0038, P0057, P0058 HO2S2 HEATERPFP:226A0
DescriptionNBS00434
SYSTEM DESCRIPTION
The ECM performs ON/OFF control of the heated oxygen sensor 2 heater corresponding to the engine speed,
amount of intake air and engine coolant temperature.
OPERATION
CONSULT-II Reference Value in Data Monitor ModeNBS00435
Specification data are reference values.
On Board Diagnosis LogicNBS00436
Sensor Input signal to ECM ECM function Actuator
Camshaft position sensor (PHASE)
Crankshaft position sensor (POS) Engine speed
Heated oxygen sensor 2
heater control Heated oxygen sensor 2 heater
Engine coolant temperature sensor Engine coolant temperature
Mass air flow sensor Amount of intake air
Engine speed rpm Heated oxygen sensor 2 heater
Above 3,600 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
MONITOR ITEM CONDITION SPECIFICATION
HO2S2 HTR (B1)
HO2S2 HTR (B2)

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 ON

Engine speed: Above 3,600 rpm OFF
DTC No.
Trouble diagnosis
name DTC detecting condition Possible cause
P0037
0037
(Bank 1) Heated oxygen
sensor 2 heater
control circuit low The current amperage in the heated oxygen sen-
sor 2 heater circuit is out of the normal range.
(An excessively low voltage signal is sent to ECM
through the heated oxygen sensor 2 heater.)

Harness or connectors
(The heated oxygen sensor 2 heater circuit is
open or shorted.)

Heated oxygen sensor 2 heater
P0057
0057
(Bank 2)
P0038
0038
(Bank 1) Heated oxygen
sensor 2 heater
control circuit high The current amperage in the heated oxygen sen-
sor 2 heater circuit is out of the normal range.
(An excessively high voltage signal is sent to
ECM through the heated oxygen sensor 2
heater.)

Harness or connectors
(The heated oxygen sensor 2 heater circuit is
shorted.)

Heated oxygen sensor 2 heater
P0058
0058
(Bank 2)

EC-860
[VK45DE]
DTC P0101 MAF SENSOR
Revision: 2006 July 2007 FX35/FX45
DTC Confirmation ProcedureNBS0043F
Perform PROCEDURE FOR MALFUNCTION A first.
If 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.
PROCEDURE FOR MALFUNCTION A
NOTE:
If engine will not start or stops soon, wait at least 10 seconds with engine stopped (Ignition switch ON) instead
of running engine at idle speed.
With CONSULT-II
1. Turn ignition switch ON.
2. Select “DATA MONITOR” mode with CONSULT-II.
3. Start engine and warm it up to normal operating temperature.
4. Run engine for at least 10 seconds at idle speed.
5. If 1st trip DTC is detected, go to EC-863, "
Diagnostic Procedure"
.
With GST
Follow the procedure “With CONSULT-II” above.
PROCEDURE FOR MALFUNCTION B
CAUTION:
Always drive vehicle at a safe speed.
With CONSULT-II
1. Turn ignition switch ON.
2. Start engine and warm it up to normal operating temperature. If engine cannot be started, go to EC-863, "
Diagnostic Procedure" .
3. Select “DATA MONITOR” mode with CONSULT-II.
4. Check the voltage of “MAS A/F SE-B1” with “DATA MONITOR”.
5. Increases engine speed to about 4,000 rpm.
6. Monitor the linear voltage rise in response to engine speed increases.
If NG, go to EC-863, "
Diagnostic Procedure" .
If OK, go to following step.
SEF174Y
SEF243Y

DTC P0101 MAF SENSOR EC-861
[VK45DE]
C
D E
F
G H
I
J
K L
M A
EC
Revision: 2006 July 2007 FX35/FX45
7. Maintain the following conditions for at least 10 consecutive sec-
onds.
8. If 1st trip DTC is detected, go to EC-863, "
Diagnostic Procedure"
.
Overall Function CheckNBS0043G
PROCEDURE FOR MALFUNCTION B
Use this procedure to check the overall function of the mass air flow sensor circuit. During this check, a DTC
might not be confirmed.
With GST
1. Start engine and warm it up to normal operating temperature.
2. Select “Service $01” with GST.
3. Check the mass air flow sensor signal with “Service $01”.
4. Check for linear mass air flow sensor signal value rise in response to increases to about 4,000 rpm in engine speed.
5. If NG, go to EC-863, "
Diagnostic Procedure" .
ENG SPEED More than 2,000 rpm
THRTL SEN 1 More than 3V
THRTL SEN 2 More than 3V
Selector lever Suitable position
Driving location Driving vehicle uphill (Increased engine load) will help
maintain the driving conditions required for this test.
PBIB0199E
SEF534P

EC-866
[VK45DE]
DTC P0101 MAF SENSOR
Revision: 2006 July 2007 FX35/FX45
Component InspectionNBS0043J
MASS AIR FLOW SENSOR
With CONSULT-II
1. Reconnect all harness connectors disconnected.
2. Start engine and warm it up to normal operating temperature.
3. Connect CONSULT-II and select “DATA MONITOR” mode.
4. Select “MAS A/F SE-B1” and check indication under the follow- ing conditions.
*: Check for linear voltage rise in response to engine being increased to about
4,000 rpm.
5. If the voltage is out of specification, proceed the following.
a. Check for the cause of uneven air flow through mass air flow sensor. Refer to following.

Crushed air ducts

Malfunctioning seal of air cleaner element

Uneven dirt of air cleaner element

Improper specification of intake air system parts
b. If NG, repair or replace malfunctioning part and perform step 2 to 4 again. If OK, go to next step.
6. Turn ignition switch OFF.
7. Disconnect mass air flow sensor harness connector and reconnect it again.
8. Perform step 2 to 4 again.
9. If NG, clean or replace mass air flow sensor.
Without CONSULT-II
1. Reconnect all harness connectors disconnected.
2. Start engine and warm it up to normal operating temperature.
3. Check voltage between ECM terminal 51 (Mass air flow sensor signal) and ground.
*: Check for linear voltage rise in response to engine being increased to about
4,000 rpm.
4. If the voltage is out of specification, proceed the following.
a. Check for the cause of uneven air flow through mass air flow sensor. Refer to following.

Crushed air ducts

Malfunctioning seal of air cleaner element

Uneven dirt of air cleaner element

Improper specification of intake air system parts
Condition MAS A/F SE-B1 (V)
Ignition switch ON (Engine stopped.) Approx. 0.4
Idle (Engine is warmed-up to normal
operating temperature.) 1.0 - 1.3
2,500 rpm (Engine is warmed-up to
normal operating temperature.) 1.6 - 2.0
Idle to about 4,000 rpm 1.0 - 1.3 to Approx. 2.4*
PBIB2371E
Condition Voltage V
Ignition switch ON (Engine stopped.) Approx. 0.4
Idle (Engine is warmed-up to normal
operating temperature.) 1.0 - 1.3
2,500 rpm (Engine is warmed-up to
normal operating temperature.) 1.6 - 2.0
Idle to about 4,000 rpm 1.0 - 1.3 to Approx. 2.4*
PBIB1106E

DTC P0102, P0103 MAF SENSOR EC-873
[VK45DE]
C
D E
F
G H
I
J
K L
M A
EC
Revision: 2006 July 2007 FX35/FX45
6. CHECK MAF SENSOR GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check harness continuity between MAF sensor terminal 3 and ECM terminal 67. Refer to Wiring Diagram.
4. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 7.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
7. CHECK MAF SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Check harness continuity between MAF sensor terminal 4 and ECM terminal 51. Refer to Wiring Diagram.
2. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 8.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
8. CHECK MASS AIR FLOW SENSOR
Refer to EC-873, "
Component Inspection" .
OK or NG
OK >> GO TO 9.
NG >> Replace mass air flow sensor.
9. CHECK INTERMITTENT INCIDENT
Refer to EC-812, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
>> INSPECTION END
Component InspectionNBS0043R
MASS AIR FLOW SENSOR
With CONSULT-II
1. Reconnect all harness connectors disconnected.
2. Start engine and warm it up to normal operating temperature.
3. Connect CONSULT-II and select “DATA MONITOR” mode.
4. Select “MAS A/F SE-B1” and check indication under the follow- ing conditions.
*: Check for linear voltage rise in response to engine being increased to about
4,000 rpm.
5. If the voltage is out of specification, proceed the following. Continuity should exist.
Continuity should exist.
Condition MAS A/F SE-B1 (V)
Ignition switch ON (Engine stopped.) Approx. 0.4
Idle (Engine is warmed-up to normal
operating temperature.) 1.0 - 1.3
2,500 rpm (Engine is warmed-up to
normal operating temperature.) 1.6 - 2.0
Idle to about 4,000 rpm 1.0 - 1.3 to Approx. 2.4*
PBIB2371E

EC-874
[VK45DE]
DTC P0102, P0103 MAF SENSOR
Revision: 2006 July 2007 FX35/FX45
a. Check for the cause of uneven air flow through mass air flow sensor. Refer to following.

Crushed air ducts

Malfunctioning seal of air cleaner element

Uneven dirt of air cleaner element

Improper specification of intake air system parts
b. If NG, repair or replace malfunctioning part and perform step 2 to 4 again. If OK, go to next step.
6. Turn ignition switch OFF.
7. Disconnect mass air flow sensor harness connector and reconnect it again.
8. Perform step 2 to 4 again.
9. If NG, clean or replace mass air flow sensor.
Without CONSULT-II
1. Reconnect all harness connectors disconnected.
2. Start engine and warm it up to normal operating temperature.
3. Check voltage between ECM terminal 51 (Mass air flow sensor signal) and ground.
*: Check for linear voltage rise in response to engine being increased to about
4,000 rpm.
4. If the voltage is out of specification, proceed the following.
a. Check for the cause of uneven air flow through mass air flow sensor. Refer to following.

Crushed air ducts

Malfunctioning seal of air cleaner element

Uneven dirt of air cleaner element

Improper specification of intake air system parts
b. If NG, repair or replace malfunctioning part and perform step 2 and 3 again. If OK, go to next step.
5. Turn ignition switch OFF.
6. Disconnect mass air flow sensor harness connector and reconnect it again.
7. Perform step 2 and 3 again.
8. If NG, clean or replace mass air flow sensor.
Removal and InstallationNBS0043S
MASS AIR FLOW SENSOR
Refer to EM-177, "AIR CLEANER AND AIR DUCT" .
Condition Voltage V
Ignition switch ON (Engine stopped.) Approx. 0.4
Idle (Engine is warmed-up to normal
operating temperature.) 1.0 - 1.3
2,500 rpm (Engine is warmed-up to
normal operating temperature.) 1.6 - 2.0
Idle to about 4,000 rpm 1.0 - 1.3 to Approx. 2.4*
PBIB1106E

DTC P0112, P0113 IAT SENSOR EC-875
[VK45DE]
C
D E
F
G H
I
J
K L
M A
EC
Revision: 2006 July 2007 FX35/FX45
DTC P0112, P0113 IAT SENSORPFP:22630
Component DescriptionNBS0043T
The intake air temperature sensor is built-into mass air flow sensor.
The sensor detects intake air temperature and transmits a signal to
the ECM.
The temperature sensing unit uses a thermistor which is sensitive to
the change in temperature. Electrical resistance of the thermistor
decreases in response to the temperature rise.

*: These data are reference values and are measured between ECM terminal 34
(Intake air temperature sensor) and ground.
CAUTION:
Do not use ECM ground terminals when measuring input/output
voltage. Doing so may result in damage to the ECM's transistor.
Use a ground other than ECM terminals, such as the ground.
On Board Diagnosis LogicNBS0043U
DTC Confirmation ProcedureNBS0043V
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.
WITH CONSULT-II
1. Turn ignition switch ON.
2. Select “DATA MONITOR” mode with CONSULT-II.
3. Wait at least 5 seconds.
4. If 1st trip DTC is detected, go to EC-878, "
Diagnostic Procedure"
.
PBIB1604E
Intake air temperature
° C ( °F) Voltage* V Resistance k
Ω
25 (77) 3.3 1.800 - 2.200
80 (176) 1.2 0.283 - 0.359
SEF012P
DTC No. Trouble diagnosis
name DTC detecting condition Possible cause
P0112
0112 Intake air tempera-
ture sensor circuit
low input An excessively low voltage from the sensor is
sent to ECM.

Harness or connectors
(The sensor circuit is open or shorted.)

Intake air temperature sensor
P0113
0113 Intake air tempera-
ture sensor circuit
high input An excessively high voltage from the sensor is
sent to ECM.
SEF058Y

EC-886
[VK45DE]
DTC P0122, P0123 TP SENSOR
Revision: 2006 July 2007 FX35/FX45
DTC P0122, P0123 TP SENSORPFP:16119
Component DescriptionNBS00447
Electric throttle control actuator consists of throttle control motor,
throttle position sensor, etc. The throttle position sensor responds to
the throttle valve movement.
The throttle position sensor has the two sensors. These sensors are
a kind of potentiometers which transform the throttle valve position
into output voltage, and emit the voltage signal to the ECM. In addi-
tion, these sensors detect the opening and closing speed of the
throttle valve and feed the voltage signals to the ECM. The ECM
judges the current opening angle of the throttle valve from these sig-
nals and the ECM controls the throttle control motor to make the
throttle valve opening angle properly in response to driving condi-
tion.
CONSULT-II Reference Value in Data Monitor ModeNBS00448
Specification data are reference values.
*: Throttle position sensor 2 signal is converted by ECM internally. Thus, it differs from ECM terminal voltage signal.
On Board Diagnosis LogicNBS00449
These self-diagnoses have the one trip detection logic.
FAIL-SAFE MODE
When the malfunction is detected, ECM enters fail-safe mode and the MIL lights up.
PBIB0145E
MONITOR ITEM CONDITION SPECIFICATION
THRTL SEN 1
THRTL SEN 2*

Ignition switch: ON
(Engine stopped)

Selector lever: D Accelerator pedal: Fully released More than 0.36V
Accelerator pedal: Fully depressed Less than 4.75V
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0122
0122 Throttle position sensor
2 circuit low input An excessively low voltage from the TP sensor
2 is sent to ECM.

Harness or connectors
(TP sensor 2 circuit is open or shorted.)
(APP sensor 2 circuit is shorted.)

Electric throttle control actuator
(TP sensor 2)

Accelerator pedal position sensor
(APP sensor 2)
P0123
0123 Throttle position sensor
2 circuit high input An excessively high voltage from the TP sen-
sor 2 is sent to ECM.
Engine operation condition in fail-safe mode
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.

EC-896
[VK45DE]
DTC P0127 IAT SENSOR
Revision: 2006 July 2007 FX35/FX45
DTC P0127 IAT SENSORPFP:22630
Component DescriptionNBS0044L
The intake air temperature sensor is built into mass air flow sensor.
The sensor detects intake air temperature and transmits a signal to
the ECM.
The temperature sensing unit uses a thermistor which is sensitive to
the change in temperature. Electrical resistance of the thermistor
decreases in response to the temperature rise.

*: These data are reference values and are measured between ECM terminal 34
(Intake air temperature sensor) and ground.
CAUTION:
Do not use ECM ground terminals when measuring input/output
voltage. Doing so may result in damage to the ECM's transistor.
Use a ground other than ECM terminals, such as the ground.
On Board Diagnosis LogicNBS0044M
DTC Confirmation ProcedureNBS0044N
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.
CAUTION:
Always drive vehicle at a safe speed.
TESTING CONDITION:
This test may be conducted with the drive wheels lifted in the shop or by driving the vehicle. If a road
test is expected to be easier, it is unnecessary to lift the vehicle.
WITH CONSULT-II
1. Wait until engine coolant temperature is less than 90 °C (194 °F)
a. Turn ignition switch ON.
PBIB1604E
Intake air temperature ° C ( °F) Voltage* V Resistance k
Ω
25 (77) 3.3 1.800 - 2.200
80 (176) 1.2 0.283 - 0.359
SEF012P
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0127
0127 Intake air temperature
too high Rationally incorrect voltage from the sensor is
sent to ECM, compared with the voltage signal
from engine coolant temperature sensor.

Harness or connectors
(The sensor circuit is open or shorted)

Intake air temperature sensor