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![INFINITI FX35 2004 Service Manual EC-852
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DTC P0122, P0123 TP SENSOR
Revision: 2004 November 2004 FX35/FX45
2. CHECK THROTTLE POSITION SENSOR 2 POWER SUPPLY CIRCUIT-I
1. Disconnect electric throttle control actuator harness co INFINITI FX35 2004 Service Manual EC-852
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DTC P0122, P0123 TP SENSOR
Revision: 2004 November 2004 FX35/FX45
2. CHECK THROTTLE POSITION SENSOR 2 POWER SUPPLY CIRCUIT-I
1. Disconnect electric throttle control actuator harness co](/manual-img/42/57021/w960_57021-2192.png)
EC-852
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DTC P0122, P0123 TP SENSOR
Revision: 2004 November 2004 FX35/FX45
2. CHECK THROTTLE POSITION SENSOR 2 POWER SUPPLY CIRCUIT-I
1. Disconnect electric throttle control actuator harness connector.
2. Turn ignition switch ON.
3. Check voltage between electric throttle control actuator terminal
1 and ground with CONSULT-II or tester.
OK or NG
OK >> GO TO 7.
NG >> GO TO 3.
3. CHECK THROTTLE POSITION SENSOR 2 POWER SUPPLY CIRCUIT-II
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check harness continuity between electric throttle control actuator terminal 1 and ECM terminal 47.
Refer to Wiring Diagram.
OK or NG
OK >> GO TO 4.
NG >> Repair or replace open circuit.
4. CHECK THROTTLE POSITION SENSOR 2 POWER SUPPLY CIRCUIT-III
Check harness for short to power and short to ground, between the following terminals.
OK or NG
OK >> GO TO 5.
NG >> Repair short to ground or short to power in harness or connectors.
5. CHECK APP SENSOR
Refer to EC-1238, "
Component Inspection" .
OK or NG
OK >> GO TO 11.
NG >> GO TO 6.
PBIB1480E
Voltage: Approximately 5V
PBIB0082E
Continuity should exist.
ECM terminal Sensor terminal Reference Wiring Diagram
47 Electric throttle control actuator terminal 1EC-850
91 APP sensor terminal 4EC-1234
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![INFINITI FX35 2004 Service Manual DTC P0122, P0123 TP SENSOR
EC-853
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6. REPLACE ACCELERATOR PEDAL ASSEMBLY
1. Replace accelerator pedal assembly.
2. Perform EC-6 INFINITI FX35 2004 Service Manual DTC P0122, P0123 TP SENSOR
EC-853
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6. REPLACE ACCELERATOR PEDAL ASSEMBLY
1. Replace accelerator pedal assembly.
2. Perform EC-6](/manual-img/42/57021/w960_57021-2193.png)
DTC P0122, P0123 TP SENSOR
EC-853
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6. REPLACE ACCELERATOR PEDAL ASSEMBLY
1. Replace accelerator pedal assembly.
2. Perform EC-698, "
Accelerator Pedal Released Position Learning" .
3. Perform EC-698, "
Throttle Valve Closed Position Learning" .
4. Perform EC-698, "
Idle Air Volume Learning" .
>>INSPECTION END
7. CHECK THROTTLE POSITION SENSOR 2 GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check harness continuity between electric throttle control actuator terminal 5 and ECM terminal 66.
Refer to Wiring Diagram.
4. 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 THROTTLE POSITION SENSOR 2 INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Check harness continuity between electric throttle control actuator terminal 2 and ECM terminal 69.
Refer to Wiring Diagram.
2. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 9.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
9. CHECK THROTTLE POSITION SENSOR
Refer to EC-854, "
Component Inspection" .
OK or NG
OK >> GO TO 11.
NG >> GO TO 10.
10. REPLACE ELECTRIC THROTTLE CONTROL ACTUATOR
1. Replace the electric throttle control actuator.
2. Perform EC-698, "
Throttle Valve Closed Position Learning" .
3. Perform EC-698, "
Idle Air Volume Learning" .
>>INSPECTION END
11 . CHECK INTERMITTENT INCIDENT
Refer to EC-784, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
>>INSPECTION END Continuity should exist.
Continuity should exist.
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EC-854
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DTC P0122, P0123 TP SENSOR
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Component InspectionABS00C24
THROTTLE POSITION SENSOR
1. Reconnect all harness connectors disconnected.
2. Perform EC-698, "
Throttle Valve Closed Position Learning" .
3. Turn ignition switch ON.
4. Set selector lever to D position.
5. Check voltage between ECM terminals 50 (TP sensor 1signal),
69 (TP sensor 2signal) and ground under the following condi-
tions.
6. If NG, replace electric throttle control actuator and go to the next
step.
7. Perform EC-698, "
Throttle Valve Closed Position Learning" .
8. Perform EC-698, "
Idle Air Volume Learning" .
Removal and InstallationABS00C25
ELECTRIC THROTTLE CONTROL ACTUATOR
Refer to EM-174, "INTAKE MANIFOLD" .
Terminal Accelerator pedal Voltage
50
(Throttle position sensor 1)Fully released More than 0.36V
Fully depressed Less than 4.75V
69
(Throttle position sensor 2)Fully released Less than 4.75V
Fully depressed More than 0.36V
PBIB1530E
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![INFINITI FX35 2004 Service Manual DTC P0125 ECT SENSOR
EC-855
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DTC P0125 ECT SENSORPFP:22630
Component DescriptionABS00C26
NOTE:
If DTC P0125 is displayed with P INFINITI FX35 2004 Service Manual DTC P0125 ECT SENSOR
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DTC P0125 ECT SENSORPFP:22630
Component DescriptionABS00C26
NOTE:
If DTC P0125 is displayed with P](/manual-img/42/57021/w960_57021-2195.png)
DTC P0125 ECT SENSOR
EC-855
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DTC P0125 ECT SENSORPFP:22630
Component DescriptionABS00C26
NOTE:
If DTC P0125 is displayed with P0117 or P0118, first perform the trouble diagnosis for DTC P0117 or
P0118. Refer to EC-842
.
The engine coolant temperature sensor is used to detect the engine
coolant temperature. The sensor modifies a voltage signal from the
ECM. The modified signal returns to the ECM as the engine coolant
temperature input. The sensor uses a thermistor which is sensitive to
the change in temperature. The electrical resistance of the ther-
mistor decreases as temperature increases.
*: These data are reference values and are measured between ECM terminal 73
(Engine coolant temperature sensor) 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.
On Board Diagnosis LogicABS00C27
This self-diagnosis has the one trip detection logic.
SEF594K
Engine coolant
temperature°C (°F)Voltage* V Resistance kΩ
-10 (14) 4.4 7.0 - 11.4
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
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0125
0125Insufficient engine cool-
ant temperature for
closed loop fuel control
Voltage sent to ECM from the sensor is not
practical, even when some time has passed
after starting the engine.
Engine coolant temperature is insufficient for
closed loop fuel control.
Harness or connectors
(High resistance in the circuit)
Engine coolant temperature sensor
Thermostat
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![INFINITI FX35 2004 Service Manual EC-856
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DTC P0125 ECT SENSOR
Revision: 2004 November 2004 FX35/FX45
DTC Confirmation ProcedureABS00C28
CAUTION:
Be careful not to overheat engine.
NOTE:
If DTC Confirmation Procedure has been INFINITI FX35 2004 Service Manual EC-856
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DTC P0125 ECT SENSOR
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DTC Confirmation ProcedureABS00C28
CAUTION:
Be careful not to overheat engine.
NOTE:
If DTC Confirmation Procedure has been](/manual-img/42/57021/w960_57021-2196.png)
EC-856
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DTC P0125 ECT SENSOR
Revision: 2004 November 2004 FX35/FX45
DTC Confirmation ProcedureABS00C28
CAUTION:
Be careful not to overheat engine.
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. Check that “COOLAN TEMP/S” is above 10°C (50°F).
If it is above 10°C (50°F), the test result will be OK.
If it is below 10°C (50°F), go to following step.
4. Start engine and run it for 65 minutes at idle speed.
If “COOLAN TEMP/S” increases to more than 10°C (50°F)
within 65 minutes, stop engine because the test result will
be OK.
5. If DTC is detected, go to EC-856, "
Diagnostic Procedure" .
WITH GST
Follow the procedure “WITH CONSULT-II” above.
Diagnostic ProcedureABS00C29
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 ENGINE COOLANT TEMPERATURE SENSOR
Refer to EC-857, "
Component Inspection" .
OK or NG
OK >> GO TO 3.
NG >> Replace engine coolant temperature sensor.
SEF174Y
PBIB2195E
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EC-857
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3. CHECK THERMOSTAT OPERATION
When the engine is cold [lower than 70°C (158°F)] condition, grasp INFINITI FX35 2004 Service Manual DTC P0125 ECT SENSOR
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3. CHECK THERMOSTAT OPERATION
When the engine is cold [lower than 70°C (158°F)] condition, grasp](/manual-img/42/57021/w960_57021-2197.png)
DTC P0125 ECT SENSOR
EC-857
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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.
*: 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
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![INFINITI FX35 2004 Service Manual EC-858
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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 se INFINITI FX35 2004 Service Manual EC-858
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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 se](/manual-img/42/57021/w960_57021-2198.png)
EC-858
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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.
*: 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
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b. Select “DATA MONITOR” mode with CONSULT-II.
c. Check the engine coolant temperature.
d. If INFINITI FX35 2004 Service Manual DTC P0127 IAT SENSOR
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b. Select “DATA MONITOR” mode with CONSULT-II.
c. Check the engine coolant temperature.
d. If](/manual-img/42/57021/w960_57021-2199.png)
DTC P0127 IAT SENSOR
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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