Temperature sensor INFINITI FX35 2004 Service Manual

TROUBLE DIAGNOSIS - SPECIFICATION VALUE
EC-131
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Revision: 2004 November 2004 FX35/FX45
TROUBLE DIAGNOSIS - SPECIFICATION VALUEPFP:00031
DescriptionABS006L1
The specification (SP) value indicates the tolerance of the value that is displayed in “DATA MONITOR (SPEC)”
mode of CONSULT-II during normal operation of the Engine Control System. When the value in “DATA MONI-
TOR (SPEC)” mode is within the SP value, the Engine Control System is confirmed OK. When the value in
“DATA MONITOR (SPEC)” mode is NOT within the SP value, the Engine Control System may have one or
more malfunctions.
The SP value is used to detect malfunctions that may affect the Engine Control System, but will not light the
MIL.
The SP value will be displayed for the following three items:

B/FUEL SCHDL (The fuel injection pulse width programmed into ECM prior to any learned on board cor-
rection)

A/F ALPHA-B1/B2 (The mean value of air-fuel ratio feedback correction factor per cycle)

MAS A/F SE-B1 (The signal voltage of the mass air flow sensor)
Testing ConditionABS006L2

Vehicle driven distance: More than 5,000 km (3,017 miles)

Barometric pressure: 98.3 - 104.3 kPa (1.003 - 1.064 kg/cm2 , 14.25 - 15.12 psi)

Atmospheric temperature: 20 - 30°C (68 - 86°F)

Engine coolant temperature: 75 - 95°C (167 - 203°F)

Transmission: Warmed-up*1

Electrical load: Not applied*2

Engine speed: Idle
*1: After the engine is warmed up to normal operating temperature, drive vehicle until “FLUID TEMP SE” (A/T
fluid temperature sensor signal) indicates more than 60°C (140°F).
*2: Rear window defogger switch, air conditioner switch, lighting switch are OFF. Steering wheel is straight
ahead.
Inspection ProcedureABS006L3
NOTE:
Perform “DATA MONITOR (SPEC)” mode in maximum scale display.
1. Perform EC-83, "
Basic Inspection" .
2. Confirm that the testing conditions indicated above are met.
3. Select “B/FUEL SCHDL”, “A/F ALPHA-B1”, “A/F ALPHA-B2”
and “MAS A/F SE-B1” in “DATA MONITOR (SPEC)” mode with
CONSULT-II.
4. Make sure that monitor items are within the SP value.
5. If NG, go to EC-132, "
Diagnostic Procedure" .
SEF601Z

DTC P0011, P0021 IVT CONTROL
EC-145
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Revision: 2004 November 2004 FX35/FX45
DTC P0011, P0021 IVT CONTROLPFP:23796
DescriptionABS006LE
SYSTEM DESCRIPTION
*: This signal is sent to the ECM through CAN communication line
This mechanism hydraulically controls cam phases continuously with the fixed operating angle of the intake
valve.
The ECM receives signals such as crankshaft position, camshaft position, engine speed, and engine coolant
temperature. Then, the ECM sends ON/OFF pulse duty signals to the intake valve timing control solenoid
valve depending on driving status. This makes it possible to control the shut/open timing of the intake valve to
increase engine torque in low/mid speed range and output in high-speed range.
CONSULT-II Reference Value in Data Monitor ModeABS006LF
Specification data are reference values.
Sensor Input signal to ECM ECM function Actuator
Crankshaft position sensor (POS)
Engine speed and piston position
Intake valve
timing controlIntake valve timing control
solenoid valve Camshaft position sensor (PHASE)
Engine coolant temperature sensor Engine coolant temperature
Wheel sensor* Vehicle speed
PBIB1102E
MONITOR ITEM CONDITION SPECIFICATION
INT/V TIM (B1)
INT/V TIM (B2)

Engine: After warming up

Shift lever: P or N

Air conditioner switch: OFF

No-loadIdle−5° - 5°CA
When revving engine up to 2,000 rpm
quicklyApprox. 0° - 30°CA
INT/V SOL (B1)
INT/V SOL (B2)

Engine: After warming up

Shift lever: P or N

Air conditioner switch: OFF

No-loadIdle 0% - 2%
When revving engine up to 2,000 rpm
quicklyApprox. 0% - 50%

DTC P0031, P0032, P0051, P0052 HO2S1 HEATER
EC-149
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Revision: 2004 November 2004 FX35/FX45
DTC P0031, P0032, P0051, P0052 HO2S1 HEATERPFP:22690
DescriptionABS006LJ
SYSTEM DESCRIPTION
The ECM performs ON/OFF control of the heated oxygen sensor 1 heater corresponding to the engine speed
and engine coolant temperature. The duty percent varies with engine coolant temperature when engine is
started.
OPERATION
CONSULT-II Reference Value in Data Monitor ModeABS006LK
Specification data are reference values.
On Board Diagnosis LogicABS006LL
Sensor Input signal to ECM ECM function Actuator
Camshaft position sensor (PHASE)
Crankshaft position sensor (POS)Engine speed
Heated oxygen sensor 1
heater controlHeated oxygen sensor 1 heater
Engine coolant temperature sensor Engine coolant temperature
Engine speed rpm Heated oxygen sensor 1 heater
Above 3,600 OFF
Below 3,600 after warming up ON
MONITOR ITEM CONDITION SPECIFICATION
HO2S1 HTR (B1)
HO2S1 HTR (B2)

Engine: After warming up

Engine speed: Below 3,600 rpmON

Engine speed: Above 3,600 rpm OFF
DTC No.Trouble diagnosis
nameDTC detecting condition Possible cause
P0031
0031
(Bank 1)Heated oxygen
sensor 1 heater
control circuit lowThe current amperage in the heated oxygen
sensor 1 heater circuit is out of the normal
range.
(An excessively low voltage signal is sent to
ECM through the heated oxygen sensor 1
heater.)

Harness or connectors
(The heated oxygen sensor 1 heater circuit is
open or shorted.)

Heater oxygen sensor 1 heater P0051
0051
(Bank 2)
P0032
0032
(Bank 1)Heated oxygen
sensor 1 heater
control circuit highThe current amperage in the heated oxygen
sensor 1 heater circuit is out of the normal
range.
(An excessively high voltage signal is sent to
ECM through the heated oxygen sensor 1
heater.)

Harness or connectors
(The heated oxygen sensor 1 heater circuit is
shorted.)

Heater oxygen sensor 1 heater P0052
0052
(Bank 2)

DTC P0037, P0038, P0057, P0058 HO2S2 HEATER
EC-157
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Revision: 2004 November 2004 FX35/FX45
DTC P0037, P0038, P0057, P0058 HO2S2 HEATERPFP:226A0
DescriptionABS006LR
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 ModeABS006LS
Specification data are reference values.
On Board Diagnosis LogicABS006LT
Sensor Input signal to ECM ECM function Actuator
Camshaft position sensor (PHASE)
Crankshaft position sensor (POS)Engine speed
Heated oxygen sensor 2
heater controlHeated 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 3,600OFF
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 loadON
MONITOR ITEM CONDITION SPECIFICATION
HO2S2 HTR (B1)
HO2S2 HTR (B2)

Engine speed is 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 loadON

Engine speed: Above 3,600 rpm OFF
DTC No.Trouble diagnosis
nameDTC detecting condition Possible cause
P0037
0037
(Bank 1)Heated oxygen
sensor 2 heater
control circuit lowThe 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.)

Heater oxygen sensor 2 heater P0057
0057
(Bank 2)
P0038
0038
(Bank 1)Heated oxygen
sensor 2 heater
control circuit highThe 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.)

Heater oxygen sensor 2 heater P0058
0058
(Bank 2)

DTC P0101 MAF SENSOR
EC-165
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Revision: 2004 November 2004 FX35/FX45
DTC P0101 MAF SENSORPFP:22680
Component DescriptionABS006LZ
The mass air flow sensor is placed in the stream of intake air. It mea-
sures the intake flow rate by measuring a part of the entire intake
flow. The mass air flow sensor controls the temperature of the hot
wire to a certain amount. The heat generated by the hot wire is
reduced as the intake air flows around it. The more air, the greater
the heat loss.
Therefore, the electric current supplied to hot wire is changed to
maintain the temperature of the hot wire as air flow increases. The
ECM detects the air flow by means of this current change.
CONSULT-II Reference Value in Data Monitor ModeABS006M0
Specification data are reference values.
On Board Diagnosis LogicABS006M1
This self-diagnosis has the one trip detection logic.
PBIB1604E
MONITOR ITEM CONDITION SPECIFICATION
MAS A/F SE-B1 See EC-131, "
TROUBLE DIAGNOSIS - SPECIFICATION VALUE" .
CAL/LD VALUE

Engine: After warming up

Shift lever: P or N

Air conditioner switch: OFF

No-loadIdle 5% - 35%
2,500 rpm 5% - 35%
MASS AIRFLOW

Engine: After warming up

Shift lever: P or N

Air conditioner switch: OFF

No-loadIdle 2.0 - 6.0 g·m/s
2,500 rpm 7.0 - 20.0 g·m/s
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0101
0101Mass air flow sensor cir-
cuit range/performance
problemA)A high voltage from the sensor is sent to ECM
under light load driving condition.

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

Mass air flow sensor
B)A low voltage from the sensor is sent to ECM
under heavy load driving condition.

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

Intake air leaks

Mass air flow sensor

EC-166
[VQ35DE]
DTC P0101 MAF SENSOR
Revision: 2004 November 2004 FX35/FX45
DTC Confirmation ProcedureABS006M2
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.
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 DTC is detected, go to EC-169, "
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-169, "
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-169, "
Diagnostic Procedure" .
If OK, go to following step.
SEF174Y
SEF243Y

DTC P0101 MAF SENSOR
EC-167
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Revision: 2004 November 2004 FX35/FX45
7. Maintain the following conditions for at least 10 consecutive sec-
onds.
8. If DTC is detected, go to EC-169, "
Diagnostic Procedure" .
Overall Function CheckABS006M3
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 MODE 1 with GST.
3. Check the mass air flow sensor signal with MODE 1.
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-169, "
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 locationDriving vehicle uphill (Increased engine load) will help
maintain the driving conditions required for this test.
PBIB0199E
SEF534P

EC-172
[VQ35DE]
DTC P0101 MAF SENSOR
Revision: 2004 November 2004 FX35/FX45
Component InspectionABS006M6
MASS AIR FLOW SENSOR
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.

Turn ignition switch OFF.

Disconnect mass air flow sensor harness connector and reconnect it again.

Perform steps 2 and 3 again.
5. If NG, remove mass air flow sensor from air duct. Check hot wire for damage or dust.
6. If NG, clean or replace mass air flow sensor.
Removal and InstallationABS006M7
MASS AIR FLOW SENSOR
Refer to EM-17, "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.)0.9 - 1.2
2,500 rpm (Engine is warmed-up to
normal operating temperature.)1.6 - 1.9
Idle to about 4,000 rpm* 0.9 - 1.2 to Approx. 2.4
PBIB1106E

DTC P0102, P0103 MAF SENSOR
EC-173
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Revision: 2004 November 2004 FX35/FX45
DTC P0102, P0103 MAF SENSORPFP:22680
Component DescriptionABS006M8
The mass air flow sensor is placed in the stream of intake air. It mea-
sures the intake flow rate by measuring a part of the entire intake
flow. The mass air flow sensor controls the temperature of the hot
wire to a certain amount. The heat generated by the hot wire is
reduced as the intake air flows around it. The more air, the greater
the heat loss.
Therefore, electric current is supplied to hot wire is changed to main-
tain the temperature of the hot wire as air flow increases. The ECM
detects the air flow by means of this current change.
CONSULT-II Reference Value in Data Monitor ModeABS006M9
Specification data are reference values.
On Board Diagnosis LogicABS006MA
These self-diagnoses have the one trip detection logic.
FAIL-SAFE MODE
When the malfunction is detected, the ECM enters fail-safe mode and the MIL lights up.
PBIB1604E
MONITOR ITEM CONDITION SPECIFICATION
MAS A/F SE-B1 See EC-131, "
TROUBLE DIAGNOSIS - SPECIFICATION VALUE" .
CAL/LD VALUE

Engine: After warming up

Shift lever: P or N

Air conditioner switch: OFF

No-loadIdle 5% - 35%
2,500 rpm 5% - 35%
MASS AIRFLOW

Engine: After warming up

Shift lever: P or N

Air conditioner switch: OFF

No-loadIdle 2.0 - 6.0 g·m/s
2,500 rpm 7.0 - 20.0 g·m/s
DTC No.Trouble diagnosis
nameDTC detecting condition Possible cause
P0102
0102Mass air flow sensor
circuit low inputAn excessively low voltage from the sensor is
sent to ECM.

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

Intake air leaks

Mass air flow sensor
P0103
0103Mass air flow sensor
circuit high inputAn excessively high voltage from the sensor is
sent to ECM.

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

Mass air flow sensor
Detected items Engine operating condition in fail-safe mode
Mass air flow sensor circuit Engine speed will not rise more than 2,400 rpm due to the fuel cut.

DTC P0102, P0103 MAF SENSOR
EC-179
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Revision: 2004 November 2004 FX35/FX45
Component InspectionABS006ME
MASS AIR FLOW SENSOR
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.

Turn ignition switch OFF.

Disconnect mass air flow sensor harness connector and reconnect it again.

Perform steps 2 and 3 again.
5. If NG, remove mass air flow sensor from air duct. Check hot wire for damage or dust.
6. If NG, clean or replace mass air flow sensor.
Removal and InstallationABS006MF
MASS AIR FLOW SENSOR
Refer to EM-17, "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.)0.9 - 1.2
2,500 rpm (Engine is warmed-up to
normal operating temperature.)1.6 - 1.9
Idle to about 4,000 rpm* 0.9 - 1.2 to Approx. 2.4
PBIB1106E