Nissan Xterra. Manual - part 250

EC-126

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INSPECTION AND ADJUSTMENT

• Transmission: Warmed-up

- With CONSULT: Drive vehicle until “ATF TEMP SE” in “DATA MONITOR” mode of “A/T” system indicates

less than 0.9 V.

- Without CONSULT: Drive vehicle for 10 minutes.

OPERATION PROCEDURE

 With CONSULT

1. Perform 

EC-125, "Accelerator Pedal Released Position Learning"

.

2. Perform 

EC-125, "Throttle Valve Closed Position Learning"

.

3. Start engine and warm it up to normal operating temperature.
4. Check that all items listed under the topic PREPARATION (previously mentioned) are in good order.
5. Select “IDLE AIR VOL LEARN” in “WORK SUPPORT” mode.

6. Touch “START” and wait 20 seconds.

7. Check that “CMPLT” is displayed on CONSULT screen. If “CMPLT” is not displayed, Idle Air Volume

Learning will not be carried out successfully. In this case, find the cause of the incident by referring to the

Diagnostic Procedure below.

8. Rev up the engine two or three times and check that idle speed and ignition timing are within the specifi-

cations.

 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 

EC-125, "Accelerator Pedal Released Position Learning"

.

2. Perform 

EC-125, "Throttle Valve Closed Position Learning"

.

3. Start engine and warm it up to normal operating temperature.
4. Check that all items listed under the topic PREPARATION (previously mentioned) are in good order.
5. Turn ignition switch OFF and wait at least 10 seconds.
6. Confirm that accelerator pedal is fully released, then turn ignition switch ON and wait 3 seconds.
7. Repeat the following procedure quickly five times within 5 seconds.
a. Fully depress the accelerator pedal.
b. Fully release the accelerator pedal.
8. Wait 7 seconds, fully depress the accelerator pedal it for approx. 20 seconds until the MIL stops blinking

and turns ON.

9. Fully release the accelerator pedal within 3 seconds after the MIL turns ON.
10. Start engine and let it idle.

ITEM

SPECIFICATION

Idle speed

M/T: 625 

± 50 rpm (in Neutral position)

A/T: 625 

± 50 rpm (in P or N position)

Ignition timing

M/T: 15 

± 5° BTDC (in Neutral position)

A/T: 15 

± 5° BTDC (in P or N position)

INSPECTION AND ADJUSTMENT

EC-127

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11. Wait 20 seconds.

12. Rev up the engine two or three times and check that idle speed and ignition timing are within the specifi-

cations.

13. If idle speed and ignition timing are not within the specification, Idle Air Volume Learning will not be carried

out successfully. In this case, find the cause of the incident by referring to the DIAGNOSTIC PROCE-

DURE below.

DIAGNOSTIC PROCEDURE

If idle air volume learning cannot be performed successfully, proceed as follows:
1. Check that throttle valve is fully closed.
2. Check PCV valve operation.
3. Check that downstream of throttle valve is free from air leakage.
4. When the above three items check out OK, engine component parts and their installation condi-

tion are questionable. Check and eliminate the cause of the incident. 

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

EC-141

.

5. 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.

ITEM

SPECIFICATION

Idle speed

M/T: 625 

± 50 rpm (in Neutral position)

A/T: 625 

± 50 rpm (in P or N position)

Ignition timing

M/T: 15 

± 5° BTDC (in Neutral position)

A/T: 15 

± 5° BTDC (in P or N position)

SEC897C

EC-128

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MIXTURE RATIO SELF-LEARNING VALUE CLEAR

MIXTURE RATIO SELF-LEARNING VALUE CLEAR

Description

INFOID:0000000010249686

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:0000000010249687

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

HOW TO SET SRT CODE

EC-129

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HOW TO SET SRT CODE

Description

INFOID:0000000009483814

OUTLINE

In order to set all SRTs, the self-diagnoses as in the “SRT ITEM” table must have been performed at least

once. Each diagnosis may require actual driving for a long period of time under various conditions.

SRT ITEM

The table below shows required self-diagnostic items to set the SRT to “CMPLT”.

• *1: Though displayed on the CONSULT screen, “HO2S HTR” is not SRT item.

• *2: If completion of several SRTs is required, perform driving patterns (DTC confirmation procedure), one by

one based on the priority for models with CONSULT.

SRT SERVICE PROCEDURE

If a vehicle has failed the state emissions inspection due to one or more SRT items indicating “INCMP”, review

the flowchart diagnostic sequence, referring to the following flowchart.

SRT item

*1

(CONSULT indication)

Performance 

Priority

*2

Required self-diagnostic items to set the SRT to “CMPLT”

Corresponding 

DTC No.

CATALYST

2

Three way catalyst function

P0420, P0430

EVAP SYSTEM

2

EVAP control system purge flow monitoring

P0441

1

EVAP control system

P0442

2

EVAP control system

P0456

HO2S

1

Air fuel ratio (A/F) sensor 1

P014C, P014D, 
P014E, P014F, 
P015A, P015B, 
P015C, P015D

Heated oxygen sensor 2

P0137, P0157

Heated oxygen sensor 2

P0138, P0158

Heated oxygen sensor 2

P0139, P0159

EGR/VVT SYSTEM

3

Intake value timing control function

P0011, P0021