Nissan Pathfinder. Manual — part 459

EC-142

< BASIC INSPECTION >

[VQ35DE]

THROTTLE VALVE CLOSED POSITION LEARNING

THROTTLE VALVE CLOSED POSITION LEARNING

Description

INFOID:0000000009178077

Throttle Valve Closed Position Learning is a function of ECM to learn the fully closed position of the throttle

valve by monitoring the throttle position sensor output signal. It must be performed each time the harness con-

nector of electric throttle control actuator or ECM is disconnected or electric throttle control actuator is

cleaned.

Work Procedure

INFOID:0000000009178078

1.

START

WITH CONSULT

1. Turn ignition switch ON.

2. Select “CLSD THL POS LEARN” in “WORK SUPPORT” mode.

3. Follow the instructions on the CONSULT display.

4. Turn ignition switch OFF and wait at least 10 seconds.

Check that throttle valve moves during the above 10 seconds by confirming the operating sound.

WITHOUT CONSULT

1. Start the engine.

NOTE:

Coolant temperature is less than 25

°C (77°F) before engine starts.

2. Warm up the engine.

NOTE:

Warm up the engine until “COOLANT TEMP/S” on “DATA MONITOR” of CONSULT reaches more than

65

°C (149°F).

3. Turn ignition switch OFF and wait at least 10 seconds.

NOTE:

Check that throttle valve moves during the above 10 seconds by confirming the operating sound.

>> END

IDLE AIR VOLUME LEARNING

EC-143

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IDLE AIR VOLUME LEARNING

Description

INFOID:0000000009178079

Idle Air Volume Learning is a function of ECM to learn the idle air volume that keeps engine idle speed within

the specific range. It must be performed under the following conditions:

• Each time the electric throttle control actuator or ECM is replaced.

• Idle speed or ignition timing is out of the specification.

Work Procedure

INFOID:0000000009178080

1.

PRECONDITIONING

Check that all of the following conditions are satisfied.

Learning will be cancelled if any of the following conditions are missed for even a moment.

• Battery voltage: More than 12.9 V (At idle)

• Engine coolant temperature: 70 - 100

°C (158 - 212°F)

• Selector lever position: P or N

• Electric load switch: OFF

(Air conditioner, head lamp, rear window defogger)

On vehicles equipped with daytime light systems, if the parking brake is applied before the engine is

started the head lamp will not illuminate.

• Steering wheel: Neutral (Straight-ahead position)

• Vehicle speed: Stopped

• Transmission: Warmed-up

- With CONSULT: Drive vehicle until “ATF TEMP SEN” in “DATA MONITOR” mode of “CVT” system indicates

less than 0.9 V.

- Without CONSULT: Drive vehicle for 10 minutes.
Will CONSULT be used?

YES

>> GO TO 2.

NO

>> GO TO 3.

2.

PERFORM IDLE AIR VOLUME LEARNING

With CONSULT

1. Perform Accelerator Pedal Released Position Learning. Refer to

EC-141, "Work Procedure"

.

2. Perform Throttle Valve Closed Position Learning. Refer to

EC-142, "Work Procedure"

.

3. Start engine and warm it up to normal operating temperature.

4. Select “IDLE AIR VOL LEARN” in “WORK SUPPORT” mode.

5. Touch “START” and wait 20 seconds.
Is “CMPLT” displayed on CONSULT screen?

YES

>> GO TO 4.

NO

>> GO TO 5.

3.

PERFORM IDLE AIR VOLUME LEARNING

Without CONSULT

NOTE:

• It is better to count the time accurately with a clock.

• It is impossible to switch the diagnostic mode when an accelerator pedal position sensor circuit has

a malfunction.

1. Perform Accelerator Pedal Released Position Learning. Refer to

EC-141, "Work Procedure"

.

2. Perform Throttle Valve Closed Position Learning. Refer to

EC-142, "Work Procedure"

.

3. Start engine and warm it up to normal operating temperature.

4. Turn ignition switch OFF and wait at least 10 seconds.

5. Confirm that accelerator pedal is fully released, turn ignition switch ON and wait 3 seconds.

6. Repeat the following procedure quickly 5 times within 5 seconds.

-

Fully depress the accelerator pedal.

-

Fully release the accelerator pedal.

7. Wait 7 seconds, fully depress the accelerator pedal for approx. 20 seconds until the MIL stops blinking

and turns ON.

8. Fully release the accelerator pedal within 3 seconds after the MIL turns ON.

EC-144

< BASIC INSPECTION >

[VQ35DE]

IDLE AIR VOLUME LEARNING

9. Start engine and let it idle.

10. Wait 20 seconds.

>> GO TO 4.

4.

CHECK IDLE SPEED AND IGNITION TIMING

Rev up the engine 2 or 3 times and check that idle speed and ignition timing are within the specifications.

For procedure, refer to

EC-461, "Work Procedure"

and

EC-462, "Work Procedure"

.

For specifications, refer to

EC-467, "Idle Speed"

and

EC-467, "Ignition Timing"

.

Is the inspection result normal?

YES

>> INSPECTION END

NO

>> GO TO 5.

5.

DETECT MALFUNCTIONING PART-I

Check the following

• Check that throttle valve is fully closed.

• Check PCV valve operation.

• Check that downstream of throttle valve is free from air leakage.
Is the inspection result normal?

YES

>> GO TO 6.

NO

>> Repair or replace malfunctioning part.

6.

DETECT MALFUNCTIONING PART-II

Engine component parts and their installation condition are questionable. Check and eliminate the cause of

the incident.

It is useful to perform “TROUBLE DIAGNOSIS - SPECIFICATION VALUE”. Refer to

EC-165, "Description"

.

If any of the following conditions occur after the engine has started, eliminate the cause of the incident and

perform Idle Air Volume Learning again:

• Engine stalls.

• Incorrect idle.

>> INSPECTION END

SEC897C

MIXTURE RATIO SELF-LEARNING VALUE CLEAR

EC-145

< BASIC INSPECTION >

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MIXTURE RATIO SELF-LEARNING VALUE CLEAR

Description

INFOID:0000000009178081

This describes show to erase the mixture ratio self-learning value. For the actual procedure, follow the instruc-

tions in “Diagnosis Procedure”.

Work Procedure

INFOID:0000000009178082

1.

START

With CONSULT

1. Start engine and warm it up to normal operating temperature.

2. Select “SELF-LEARNING CONT” in “WORK SUPPORT” mode with CONSULT.

3. Clear mixture ratio self-learning value by touching “CLEAR”.

With GST

1. Start engine and warm it up to normal operating temperature.

2. Turn ignition switch OFF.

3. Disconnect mass air flow sensor harness connector.

4. Restart engine and let it idle for at least 5 seconds.

5. Stop engine and reconnect mass air flow sensor harness connector.

6. Select Service $03 with GST. Check that DTC P0102 is detected.

7. Select Service $04 with GST to erase the DTC P0102.

>> END