Infiniti QX56 (JA60). Manual — part 414

EC-308

< COMPONENT DIAGNOSIS >

[VK56DE]

P1226 TP SENSOR

P1226 TP SENSOR

Component Description

INFOID:0000000005149358

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 the 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 addi-

tion, 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 sig-

nals and the ECM controls the throttle control motor to make the

throttle valve opening angle properly in response to driving condi-

tion.

On Board Diagnosis Logic

INFOID:0000000005149359

The MIL will not light up for this self-diagnosis.

DTC Confirmation Procedure

INFOID:0000000005149360

NOTE:

If DTC Confirmation Procedure has been previously conducted, always perform the following procedure

before conducting the next step.
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.

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.

6. If 1st trip DTC is detected, go to

EC-308, "Diagnosis Procedure"

Diagnosis Procedure

INFOID:0000000005149361

CHECK ELECTRIC THROTTLE CONTROL ACTUATOR VISUALLY

1. Turn ignition switch OFF.

2. Remove the intake air duct.

3. Check if foreign matter is caught between the throttle valve and

the housing.

OK or NG

>> GO TO 2.

>> Remove the foreign matter and clean the electric throttle

control actuator inside.

PBIB0145E

DTC No.

Trouble diagnosis name

DTC detecting condition

Possible cause

P1226
1226

Closed throttle position learning
performance

Closed throttle position learning is not performed
successfully, repeatedly.

• Electric throttle control actuator

(TP sensor 1 and 2)

BBIA0364E

P1226 TP SENSOR

EC-309

< COMPONENT DIAGNOSIS >

[VK56DE]

REPLACE ELECTRIC THROTTLE CONTROL ACTUATOR

1. Replace the electric throttle control actuator.

2. Perform

EC-18, "Throttle Valve Closed Position Learning"

3. Perform

EC-18, "Idle Air Volume Learning"

>> INSPECTION END

EC-310

< COMPONENT DIAGNOSIS >

[VK56DE]

P1421 COLD START CONTROL

P1421 COLD START CONTROL

Description

INFOID:0000000005149362

ECM controls ignition timing and engine idle speed when engine is started with pre-warming up condition.

This control promotes the activation of three way catalyst by heating the catalyst and reduces emissions.

On Board Diagnosis Logic

INFOID:0000000005149363

If DTC P1421 is displayed with other DTC, first perform the trouble diagnosis for other DTC.

DTC Confirmation Procedure

INFOID:0000000005149364

NOTE:

If DTC Confirmation Procedure has been previously conducted, always perform the following procedure

before conducting the next step.

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 11 V at idle.

WITH CONSULT-III

1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Select “DATA MONITOR” mode with CONSULT-III.
4. Check that the “COOLAN TEMP/S” indication is between 5

°C (41°F) and 36°C (97°F).

If “COOLAN TEMP/S” indication is within the specified value, go to the following step.

If “COOLANT TEMP/S” indication is out of the specified value, cool engine down or warm engine up and

go to step 1.

5. Start engine and let it idle for 5 minutes.
6. Check 1st trip DTC.
7. If 1st trip DTC is detected, go to

EC-310, "Diagnosis Procedure"

WITH GST

Follow the procedure “WITH CONSULT-III” above.

Diagnosis Procedure

INFOID:0000000005149365

PERFORM IDLE AIR VOLUME LEARNING

Perform