Infiniti G37 Coupe. Manual - part 552

P1225, P1234 TP SENSOR

EC-389

< COMPONENT DIAGNOSIS >

[VQ37VHR]

C

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G

H

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EC

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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-389, "Special Repair Requirement"

.

>> INSPECTION END

Special Repair Requirement

INFOID:0000000001910847

1.

PERFORM THROTTLE VALVE CLOSED POSITION LEARNING

Refer to 

EC-18, "THROTTLE VALVE CLOSED POSITION LEARNING : Special Repair Requirement"

>> GO TO 2.

2.

PERFORM IDLE AIR VOLUME LEARNING

Refer to 

EC-19, "IDLE AIR VOLUME LEARNING : Special Repair Requirement"

>> END

JMBIA0025ZZ

EC-390

< COMPONENT DIAGNOSIS >

[VQ37VHR]

P1226, P1235 TP SENSOR

P1226, P1235 TP SENSOR

Description

INFOID:0000000001910844

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 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:0000000001734198

DTC DETECTION LOGIC

DTC CONFIRMATION PROCEDURE

1.

PRECONDITIONING

If DTC Confirmation Procedure has been previously conducted, always perform the following before conduct-
ing 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 10V 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-390, "Diagnosis Procedure"

.

NO

>> INSPECTION END

Diagnosis Procedure

INFOID:0000000001911018

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

(TP sensor 1 and 2)

P1235

Closed throttle position learn-
ing performance (bank 2)

P1226, P1235 TP SENSOR

EC-391

< COMPONENT DIAGNOSIS >

[VQ37VHR]

C

D

E

F

G

H

I

J

K

L

M

A

EC

N

P

O

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-391, "Special Repair Requirement"

.

>> INSPECTION END

Special Repair Requirement

INFOID:0000000001910848

1.

PERFORM THROTTLE VALVE CLOSED POSITION LEARNING

Refer to 

EC-18, "THROTTLE VALVE CLOSED POSITION LEARNING : Special Repair Requirement"

>> GO TO 2.

2.

PERFORM IDLE AIR VOLUME LEARNING

Refer to 

EC-19, "IDLE AIR VOLUME LEARNING : Special Repair Requirement"

>> END

JMBIA0025ZZ

EC-392

< COMPONENT DIAGNOSIS >

[VQ37VHR]

P1233, P2101 ELECTRIC THROTTLE CONTROL FUNCTION

P1233, P2101 ELECTRIC THROTTLE CONTROL FUNCTION

Description

INFOID:0000000001734201

Electric throttle control actuator consists of throttle control motor, throttle position sensor, etc.
The throttle control motor is operated by the ECM and it opens and closes the throttle valve.
The current opening angle of the throttle valve is detected by the throttle position sensor and it provides feed-
back to the ECM to control the throttle control motor to make the throttle valve opening angle properly in
response to driving condition.

DTC Logic

INFOID:0000000001734202

DTC DETECTION LOGIC

NOTE:
If DTC P1233 or P2101 is displayed with DTC P1238, P1290, P2100 or 2119, first perform the trouble
diagnosis for DTC P1238, P2119 or P1290, P2100. Refer to 

EC-399, "DTC Logic"

 or 

EC-404, "DTC

Logic"

.

DTC CONFIRMATION PROCEDURE

1.

PRECONDITIONING

If DTC Confirmation Procedure has been previously conducted, always perform the following before conduct-
ing 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 11V when engine
is running.

>> GO TO 2.

2.

PERFORM DTC CONFIRMATION PROCEDURE

1.

Turn ignition switch ON and wait at least 2 seconds.

2.

Start engine and let it idle for 5 seconds.

3.

Check DTC.

Is DTC detected?

YES

>> Go to 

EC-392, "Diagnosis Procedure"

.

NO

>> INSPECTION END

Diagnosis Procedure

INFOID:0000000001734203

1.

CHECK GROUND CONNECTION

1.

Turn ignition switch OFF.

2.

Check ground connection M95. Refer to Ground Inspection in 

GI-41, "Circuit Inspection"

.

Is the inspection result normal?

YES

>> GO TO 2.

NO

>> Repair or replace ground connection.

2.

CHECK THROTTLE CONTROL MOTOR RELAY INPUT SIGNAL CIRCUIT-I

Check the voltage between ECM harness connector and ground.

DTC No.

Trouble diagnosis name

DTC detecting condition

Possible cause

P1233

Electric throttle control 
performance (bank 2)

Electric throttle control function does not oper-
ate properly.

• Harness or connectors

(Throttle control motor circuit is open or 
shorted)

• Electric throttle control actuator

P2101

Electric throttle control 
performance (bank 1)