Infiniti FX35, FX50 (S51). Manual - part 709

P1225, P1234 TP SENSOR

EC-377

< DTC/CIRCUIT DIAGNOSIS >

[VQ35HR]

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P1225, P1234 TP SENSOR

Description

INFOID:0000000005236970

Electric throttle control actuator consists of throttle control motor,
throttle position (TP) sensor, etc. The throttle position sensor
responds to the throttle valve movement. 
The throttle position sensor has 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 addition,
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 signals and the
ECM controls the throttle control motor to make the throttle valve
opening angle properly in response to driving condition.

DTC Logic

INFOID:0000000005236971

DTC DETECTION LOGIC

DTC CONFIRMATION PROCEDURE

1.

PRECONDITIONING

If DTC Confirmation Procedure has been previously conducted, always perform the following procedure
before conducting the next test.
1.

Turn ignition switch OFF and wait at least 10 seconds.

2.

Turn ignition switch ON.

3.

Turn ignition switch OFF and wait at least 10 seconds.

TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 10 V at idle.

>> GO TO 2.

2.

PERFORM DTC CONFIRMATION PROCEDURE

1.

Turn ignition switch ON.

2.

Turn ignition switch OFF and wait at least 10 seconds.

3.

Turn ignition switch ON.

4.

Check 1st trip DTC.

Is 1st trip DTC detected?

YES

>> Go to 

EC-377, "Diagnosis Procedure"

.

NO

>> INSPECTION END

Diagnosis Procedure

INFOID:0000000005236972

1.

CHECK ELECTRIC THROTTLE CONTROL ACTUATOR VISUALLY

1.

Turn ignition switch OFF.

2.

Remove the intake air duct.

PBIB0145E

DTC No.

Trouble diagnosis name

DTC detecting condition

Possible cause

P1225

Closed throttle position learning per-
formance (bank 1)

Closed throttle position learning value 
is excessively low.

• Electric throttle control actuator

[Throttle position (TP) sensor 1 and 
2]

P1234

Closed throttle position learning per-
formance (bank 2)

EC-378

< DTC/CIRCUIT DIAGNOSIS >

[VQ35HR]

P1225, P1234 TP SENSOR

3.

Check if foreign matter is caught between the throttle valve (1)
and the housing.

Is the inspection result normal?

YES

>> GO TO 2.

NO

>> Remove the foreign matter and clean the electric throttle

control actuator inside.

2.

REPLACE ELECTRIC THROTTLE CONTROL ACTUATOR

1.

Replace malfunctioning electric throttle control actuator.

2.

Go to 

EC-378, "Special Repair Requirement"

.

>> INSPECTION END

Special Repair Requirement

INFOID:0000000005236973

1.

PERFORM THROTTLE VALVE CLOSED POSITION LEARNING

Refer to 

EC-25, "THROTTLE VALVE CLOSED POSITION LEARNING : Special Repair Requirement"

>> GO TO 2.

2.

PERFORM IDLE AIR VOLUME LEARNING

Refer to 

EC-25, "IDLE AIR VOLUME LEARNING : Special Repair Requirement"

>> END

JMBIA1511ZZ

P1226, P1235 TP SENSOR

EC-379

< DTC/CIRCUIT DIAGNOSIS >

[VQ35HR]

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P1226, P1235 TP SENSOR

Description

INFOID:0000000005236974

Electric throttle control actuator consists of throttle control motor,
throttle position (TP) sensor, etc. The throttle position sensor
responds to the throttle valve movement. 
The throttle position sensor has 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 addition,
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 signals and the
ECM controls the throttle control motor to make the throttle valve
opening angle properly in response to driving condition.

DTC Logic

INFOID:0000000005236975

DTC DETECTION LOGIC

DTC CONFIRMATION PROCEDURE

1.

PRECONDITIONING

If DTC Confirmation Procedure has been previously conducted, always perform the following procedure
before conducting the next test.
1.

Turn ignition switch OFF and wait at least 10 seconds.

2.

Turn ignition switch ON.

3.

Turn ignition switch OFF and wait at least 10 seconds.

TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 10 V at idle.

>> GO TO 2.

2.

PERFORM DTC CONFIRMATION PROCEDURE

1.

Turn ignition switch ON.

2.

Turn ignition switch OFF and wait at least 10 seconds.

3.

Turn ignition switch ON.

4.

Repeat steps 2 and 3 for 32 times.

5.

Check 1st trip DTC.

Is 1st trip DTC detected?

YES

>> Go to 

EC-379, "Diagnosis Procedure"

.

NO

>> INSPECTION END

Diagnosis Procedure

INFOID:0000000005236976

1.

CHECK ELECTRIC THROTTLE CONTROL ACTUATOR VISUALLY

1.

Turn ignition switch OFF.

2.

Remove the intake air duct.

PBIB0145E

DTC No.

Trouble diagnosis name

DTC detecting condition

Possible cause

P1226

Closed throttle position learn-
ing performance (bank 1)

Closed throttle position learning is not performed 
successfully, repeatedly.

• Electric throttle control actuator

[Throttle position (TP) sensor 1 
and 2]

P1235

Closed throttle position learn-
ing performance (bank 2)

EC-380

< DTC/CIRCUIT DIAGNOSIS >

[VQ35HR]

P1226, P1235 TP SENSOR

3.

Check if foreign matter is caught between the throttle valve (1)
and the housing.

Is the inspection result normal?

YES

>> GO TO 2.

NO

>> Remove the foreign matter and clean the electric throttle

control actuator inside.

2.

REPLACE ELECTRIC THROTTLE CONTROL ACTUATOR

1.

Replace malfunctioning electric throttle control actuator.

2.

Go to 

EC-380, "Special Repair Requirement"

.

>> INSPECTION END

Special Repair Requirement

INFOID:0000000005236977

1.

PERFORM THROTTLE VALVE CLOSED POSITION LEARNING

Refer to 

EC-25, "THROTTLE VALVE CLOSED POSITION LEARNING : Special Repair Requirement"

>> GO TO 2.

2.

PERFORM IDLE AIR VOLUME LEARNING

Refer to 

EC-25, "IDLE AIR VOLUME LEARNING : Special Repair Requirement"

>> END

JMBIA1511ZZ