ground INFINITI FX35 2004 Service Manual

DTC P0125 ECT SENSOR
EC-857
[VK45DE]
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Revision: 2004 November 2004 FX35/FX45
3. CHECK THERMOSTAT OPERATION
When the engine is cold [lower than 70°C (158°F)] condition, grasp lower radiator hose and confirm the engine
coolant does not flow.
OK or NG
OK >> GO TO 4.
NG >> Repair or replace thermostat. Refer to CO-51, "
THERMOSTAT AND WATER CONTROL VALVE" .
4. CHECK INTERMITTENT INCIDENT
Refer to EC-784, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
>>INSPECTION END
Component InspectionABS00C2A
ENGINE COOLANT TEMPERATURE SENSOR
1. Check resistance between engine coolant temperature sensor
terminals 1 and 2 as shown in the figure.
<Reference data>
*: These data are reference values and are measured between ECM terminal
73 (Engine coolant temperature sensor) and ground.
2. If NG, replace engine coolant temperature sensor.
Removal and InstallationABS00C2B
ENGINE COOLANT TEMPERATURE SENSOR
Refer to CO-51, "THERMOSTAT AND WATER CONTROL VALVE" .
PBIB2005E
Engine coolant
temperature°C (°F)Voltage* V Resistance kΩ
20 (68) 3.5 2.1 - 2.9
50 (122) 2.2 0.68 - 1.00
90 (194) 0.9 0.236 - 0.260
SEF012P

EC-858
[VK45DE]
DTC P0127 IAT SENSOR
Revision: 2004 November 2004 FX35/FX45
DTC P0127 IAT SENSORPFP:22630
Component DescriptionABS00C2C
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.
<Reference data>
*: 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 termi-
nals, such as the ground.
On Board Diagnosis LogicABS00C2D
DTC Confirmation ProcedureABS00C2E
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.
SEC266C
Intake air temperature
°C (°F)Voltage* V Resistance kΩ
–10 (14) 4.43 7.9 - 9.3
25 (77) 3.32 1.9 - 2.1
80 (176) 1.23 0.31 - 0.37
SEF012P
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0127
0127Intake air temperature
too highRationally 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

DTC P0127 IAT SENSOR
EC-859
[VK45DE]
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Revision: 2004 November 2004 FX35/FX45
b. Select “DATA MONITOR” mode with CONSULT-II.
c. Check the engine coolant temperature.
d. If the engine coolant temperature is not less than 90°C (194°F),
turn ignition switch OFF and cool down engine.

Perform the following steps before engine coolant tempera-
ture is above 90°C (194°F).
2. Turn ignition switch ON.
3. Select “DATA MONITOR” mode with CONSULT-II.
4. Start engine.
5. Hold vehicle speed at more than 70 km/h (43 MPH) for 100 con-
secutive seconds.
6. If 1st trip DTC is detected, go to EC-859, "
Diagnostic Procedure" .
WITH GST
Follow the procedure “WITH CONSULT-II” above.
Diagnostic ProcedureABS00C2F
1. CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten three ground screws on the body.
Refer to EC-791, "
Ground Inspection" .
OK or NG
OK >> GO TO 2.
NG >> Repair or replace ground connections.
2. CHECK INTAKE AIR TEMPERATURE SENSOR
Refer to EC-841, "
Component Inspection" .
OK or NG
OK >> GO TO 3.
NG >> Replace mass air flow sensor (with intake air temperature sensor).
3. CHECK INTERMITTENT INCIDENT
Refer to EC-784, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
>>INSPECTION END
SEF189Y
PBIB2195E

EC-866
[VK45DE]
DTC P0132, P0152 HO2S1
Revision: 2004 November 2004 FX35/FX45
Specification data are reference values and are measured between each terminal and ground.
CAUTION:
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.
TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
16 R/LHeated oxygen sensor 1
(bank 1)[Engine is running]

Warm-up condition

Engine speed is 2,000 rpm0 - Approximately 1.0V
(Periodically change)
78 B/RSensor ground
(Heated oxygen sensor)[Engine is running]

Warm-up condition

Idle speedApproximately 0V

EC-868
[VK45DE]
DTC P0132, P0152 HO2S1
Revision: 2004 November 2004 FX35/FX45
Specification data are reference values and are measured between each terminal and ground.
CAUTION:
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.
Diagnostic ProcedureABS00C2S
1. CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten three ground screws on the body.
Refer to EC-791, "
Ground Inspection" .
OK or NG
OK >> GO TO 2.
NG >> Repair or replace ground connections.
2. RETIGHTEN HEATED OXYGEN SENSOR 1
1. Loosen and retighten corresponding heated oxygen sensor 1.
>> GO TO 3.
TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
35 BRHeated oxygen sensor 1
(bank 2)[Engine is running]

Warm-up condition

Engine speed is 2,000 rpm0 - Approximately 1.0V
(Periodically change)
78 B/RSensor ground
(Heated oxygen sensor)[Engine is running]

Warm-up condition

Idle speedApproximately 0V
PBIB2195E
Tightening torque: 50 N·m (5.1 kg-m, 37 ft-lb)
PBIB1520E

DTC P0132, P0152 HO2S1
EC-869
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Revision: 2004 November 2004 FX35/FX45
3. CHECK HO2S1 GROUND CIRCUIT FOR OPEN AND SHORT
1. Disconnect heated oxygen sensor 1 harness connector.
2. Disconnect ECM harness connector.
3. Check harness continuity between HO2S1 terminal 4 and ECM terminal 78.
Refer to Wiring Diagram.
4. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 4.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
4. CHECK HO2S1 INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Check harness continuity between ECM terminal and HO2S1 terminal as follows.
Refer to Wiring Diagram.
2. Check harness continuity between the following terminals and ground.
Refer to Wiring Diagram.
3. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 5.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.Continuity should exist.
PBIB1521E
DTCTe r m i n a l s
Bank
ECM Sensor
P0132 16 1 1
P0152 35 1 2
Continuity should exist.
DTCTe r m i n a l s
Bank
ECM Sensor
P0132 16 1 1
P0152 35 1 2
Continuity should not exist.

DTC P0132, P0152 HO2S1
EC-871
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Revision: 2004 November 2004 FX35/FX45
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.
Without CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Set voltmeter probes between ECM terminal 16 [HO2S1 (B1) signal] or 35 [HO2S1 (B2) signal] and
ground.
3. Check the following with engine speed held at 2,000 rpm con-
stant under no load.

The voltage fluctuates between 0 to 0.3V and 0.6 to 1.0V
more than 5 times within 10 seconds.

The maximum voltage is over 0.6V at least 1 time.

The minimum voltage is below 0.3V at least 1 time.

The voltage never exceeds 1.0V.
1 time: 0 - 0.3V → 0.6 - 1.0V → 0 - 0.3V
2 times: 0 - 0.3V → 0.6 - 1.0V → 0 - 0.3V → 0.6 - 1.0V → 0 -
0.3V
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 InstallationABS00C2U
HEATED OXYGEN SENSOR 1
Refer to EM-178, "EXHAUST MANIFOLD AND THREE WAY CATALYST" .
SEF648Y
PBIB1528E

EC-874
[VK45DE]
DTC P0133, P0153 HO2S1
Revision: 2004 November 2004 FX35/FX45
7. Make sure that “OK” is displayed after touching “SELF-DIAG
RESULTS”. If “NG” is displayed, refer to EC-878, "
Diagnostic
Procedure" .
Overall Function CheckABS00C2Z
Use this procedure to check the overall function of the heated oxygen sensor 1 circuit. During this check, a 1st
trip DTC might not be confirmed.
WITH GST
1. Start engine and warm it up to normal operating temperature.
2. Set voltmeter probes between ECM terminal 16 [HO2S1(B1) signal] or 35 [HO2S1(B2) signal] and
ground.
3. Check the following with engine speed held at 2,000 rpm con-
stant under no load.
–The voltage fluctuates between 0 to 0.3V and 0.6 to 1.0V more
than 5 times within 10 seconds.
4. If NG, go to EC-878, "
Diagnostic Procedure" .
SEF658Y
1 time: 0 - 0.3V → 0.6 - 1.0V → 0 - 0.3V
2 times: 0 - 0.3V → 0.6 - 1.0V → 0 - 0.3V → 0.6 - 1.0V
→ 0 - 0.3V
PBIB1528E

EC-876
[VK45DE]
DTC P0133, P0153 HO2S1
Revision: 2004 November 2004 FX35/FX45
Specification data are reference values and are measured between each terminal and ground.
CAUTION:
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.
TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
16 R/LHeated oxygen sensor 1
(bank 1)[Engine is running]

Warm-up condition

Engine speed is 2,000 rpm0 - Approximately 1.0V
(Periodically change)
78 B/RSensor ground
(Heated oxygen sensor)[Engine is running]

Warm-up condition

Idle speedApproximately 0V

EC-878
[VK45DE]
DTC P0133, P0153 HO2S1
Revision: 2004 November 2004 FX35/FX45
Specification data are reference values and are measured between each terminal and ground.
CAUTION:
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.
Diagnostic ProcedureABS00C31
1. CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten three ground screws on the body.
Refer to EC-791, "
Ground Inspection" .
OK or NG
OK >> GO TO 2.
NG >> Repair or replace ground connections.
2. RETIGHTEN HEATED OXYGEN SENSOR 1
Loosen and retighten heated oxygen sensor 1.
>> GO TO 3.
TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
35 BRHeated oxygen sensor 1
(bank 2)[Engine is running]

Warm-up condition

Engine speed is 2,000 rpm0 - Approximately 1.0V
(Periodically change)
78 B/RSensor ground
(Heated oxygen sensor)[Engine is running]

Warm-up condition

Idle speedApproximately 0V
PBIB2195E
Tightening torque: 50 N·m (5.1 kg-m, 37 ft-lb)
PBIB1520E