Nissan Frontier. Manual - part 386

DIAGNOSIS AND REPAIR WORK FLOW

EC-115

< BASIC INSPECTION >

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Are they within the SP value?

YES

>> GO TO 9.

NO

>> GO TO 8.

8.

DETECT MALFUNCTIONING PART BY TROUBLE DIAGNOSIS - SPECIFICATION VALUE

Detect malfunctioning part according to 

EC-138, "Diagnosis Procedure"

.

Is a malfunctioning part detected?

YES

>> GO TO 11.

NO

>> GO TO 9.

9.

DETECT MALFUNCTIONING SYSTEM BY SYMPTOM MATRIX CHART

Detect malfunctioning system according to 

EC-461, "Symptom Matrix Chart"

 based on the confirmed symptom

in step 4, and determine the trouble diagnosis order based on possible causes and symptoms.

>> GO TO 10.

10.

DETECT MALFUNCTIONING PART BY DIAGNOSTIC PROCEDURE

Inspect according to Diagnostic Procedure of the system.

NOTE:

The Diagnostic Procedure in EC section described based on open circuit inspection. A short circuit inspection

is also required for the circuit check in the Diagnostic Procedure. For details, refer to Circuit Inspection in 

GI-

39, "How to Check Terminal"

.

Is a malfunctioning part detected?

YES

>> GO TO 11.

NO

>> Monitor input data from related sensors or check voltage of related ECM terminals using CON-

SULT. Refer to 

EC-68, "CONSULT Reference Value in Data Monitor Mode"

, 

EC-71, "ECM Termi-

nal and Reference Value"

.

11.

REPAIR OR REPLACE THE MALFUNCTIONING PART

1. Repair or replace the malfunctioning part.

2. Reconnect parts or connectors disconnected during Diagnostic Procedure again after repair and replace-

ment.

3. Check DTC. If DTC is displayed, erase it, refer to 

EC-82, "DTC Index"

.

>> GO TO 12.

12.

FINAL CHECK

When DTC was detected in step 2, perform DTC Confirmation Procedure or Overall Function Check again,

and then make sure that the malfunction have been completely repaired.

When symptom was described from the customer, refer to confirmed symptom in step 3 or 4, and make sure

that the symptom is not detected.
Is DTC detected and does symptom remain?

YES-1 (DTC is detected)>>GO TO 10.

YES-2 (Symptom remains)>>GO TO 6.

NO-1 (No request for I/M examination from the customer)>>Before returning the vehicle to the customer,

always erase unnecessary DTC in ECM and TCM (Transmission Control Module).

NO-2 (I/M examination, requested from the customer)>>GO TO 13.

13.

PREPARE FOR I/M EXAMINATION

1. Set SRT codes. Refer to 

EC-126, "Description"

.

2. Erase permanent DTCs. Refer to 

EC-132, "Description"

.

>> INSPECTION END

DIAGNOSTIC WORKSHEET

Description

EC-116

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DIAGNOSIS AND REPAIR WORK FLOW

There are many operating conditions that lead to the malfunction of

engine components. A good grasp of such conditions can make trou-

bleshooting faster and more accurate.

In general, each customer feels differently about an incident. It is

important to fully understand the symptoms or conditions for a cus-

tomer complaint.

Utilize a diagnostic worksheet like the one on the next page in order

to organize all the information for troubleshooting.

Some conditions may cause the MIL to come on steady or blink, and

DTC to be detected. Examples:

• Vehicle ran out of fuel, which caused the engine to misfire.

• Fuel filler cap was left off or incorrectly screwed on, allowing fuel to

evaporate into the atmosphere.

Worksheet Sample

SEF907L

MTBL0017

INSPECTION AND ADJUSTMENT

EC-117

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INSPECTION AND ADJUSTMENT

Basic Inspection

INFOID:0000000009480755

1.

INSPECTION START

1. Check service records for any recent repairs that may indicate a related malfunction, or a current need for

scheduled maintenance.

2. Open engine hood and check the following:

-

Harness connectors for improper connections

-

Wiring harness for improper connections, pinches and cut

-

Vacuum hoses for splits, kinks and improper connections

-

Hoses and ducts for leakage

-

Air cleaner clogging

-

Gasket

3. Check that electrical or mechanical loads are not applied.

-

Headlamp switch is OFF.

-

Air conditioner switch is OFF.

-

Steering wheel is in the straight-ahead position, etc.

4. Start engine and warm it up until engine coolant temperature

indicator points to the middle of gauge.

Ensure engine stays below 1,000 rpm.

5. Run engine at about 2,000 rpm for about 2 minutes under no

load.

6. Make sure that no DTC is displayed with CONSULT or GST.
OK or NG

OK

>> GO TO 3.

NG

>> GO TO 2.

2.

REPAIR OR REPLACE

Repair or replace components as necessary according to corresponding Diagnostic Procedure.

>> GO TO 3.

3.

CHECK TARGET IDLE SPEED

With CONSULT

1. Run engine at about 2,000 rpm for about 2 minutes under no load.

SEF983U

SEF976U

SEF977U

EC-118

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INSPECTION AND ADJUSTMENT

2. Rev engine (2,000 to 3,000 rpm) two or three times under no

load, then run engine at idle speed for about 1 minute.

3. Read idle speed in “DATA MONITOR” mode with CONSULT. Refer to 

EC-121, "Idle Speed and Ignition

Timing Check"

.

 Without CONSULT

1. Run engine at about 2,000 rpm for about 2 minutes under no load.

2. Rev engine (2,000 to 3,000 rpm) two or three times under no load, then run engine at idle speed for about

1 minute.

3. Check idle speed. Refer to 

EC-121, "Idle Speed and Ignition Timing Check"

.

OK or NG

OK

>> GO TO 10.

NG

>> GO TO 4.

4.

PERFORM ACCELERATOR PEDAL RELEASED POSITION LEARNING 

1. Stop engine.

2. Perform 

EC-123, "Accelerator Pedal Released Position Learning"

.

>> GO TO 5.

5.

PERFORM THROTTLE VALVE CLOSED POSITION LEARNING

Perform 

EC-123, "Throttle Valve Closed Position Learning"

.

>> GO TO 6.

6.

PERFORM IDLE AIR VOLUME LEARNING

Refer to 

EC-124, "Idle Air Volume Learning"

.

Is Idle Air Volume Learning carried out successfully?
Yes or No

Yes

>> GO TO 7.

No

>> 1. Follow the instruction of Idle Air Volume Learning.

2. GO TO 4.

7.

CHECK TARGET IDLE SPEED AGAIN

 With CONSULT

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

2. Read idle speed in “DATA MONITOR” mode with CONSULT. Refer to 

EC-121, "Idle Speed and Ignition

Timing Check"

.

PBIA8513J

M/T: 625 

± 50 rpm (in Neutral position)

A/T: 700 

± 50 rpm (in P or N position)

M/T: 625 

± 50 rpm (in Neutral position)

A/T: 700 

± 50 rpm (in P or N position)