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Nissan Pathfinder (2008 year). Manual - part 302

ON BOARD DIAGNOSTIC (OBD) SYSTEM

EC-533

< FUNCTION DIAGNOSIS >

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HOW TO ERASE EMISSION-RELATED DIAGNOSTIC INFORMATION

How to Erase DTC

WITH CONSULT-III

The emission related diagnostic information in the ECM can be erased by selecting “All Erase” in the “Descrip-
tion” of “FINAL CHECK” mode with CONSULT-III.

WITH GST

The emission related diagnostic information in the ECM can be erased by selecting Service $04 with GST.
NOTE:
If the DTC is not for A/T related items (see

EC-919, "DTC Index"

), skip step 2.

MISFIRE

A2H

No.1 Cylinder Misfire

P0301

0BH

24H

EWMA (Exponential Weighted
Moving Average) misfire counts
for last 10 driving cycles

P0301

0CH

24H

Misfire counts for last/current driv-
ing cycles

A3H

No.2 Cylinder Misfire

P0302

0BH

24H

EWMA (Exponential Weighted
Moving Average) misfire counts
for last 10 driving cycles

P0302

0CH

24H

Misfire counts for last/current driv-
ing cycles

A4H

No.3 Cylinder Misfire

P0303

0BH

24H

EWMA (Exponential Weighted
Moving Average) misfire counts
for last 10 driving cycles

P0303

0CH

24H

Misfire counts for last/current driv-
ing cycles

A5H

No.4 Cylinder Misfire

P0304

0BH

24H

EWMA (Exponential Weighted
Moving Average) misfire counts
for last 10 driving cycles

P0304

0CH

24H

Misfire counts for last/current driv-
ing cycles

A6H

No.5 Cylinder Misfire

P0305

0BH

24H

EWMA (Exponential Weighted
Moving Average) misfire counts
for last 10 driving cycles

P0305

0CH

24H

Misfire counts for last/current driv-
ing cycles

A7H

No.6 Cylinder Misfire

P0306

0BH

24H

EWMA (Exponential Weighted
Moving Average) misfire counts
for last 10 driving cycles

P0306

0CH

24H

Misfire counts for last/current driv-
ing cycles

A8H

No.7 Cylinder Misfire

P0307

0BH

24H

EWMA (Exponential Weighted
Moving Average) misfire counts
for last 10 driving cycles

P0307

0CH

24H

Misfire counts for last/current driv-
ing cycles

A9H

No.8 Cylinder Misfire

P0308

0BH

24H

EWMA (Exponential Weighted
Moving Average) misfire counts
for last 10 driving cycles

P0308

0CH

24H

Misfire counts for last/current driv-
ing cycles

Item

OBD-

MID

Self-diagnostic test item

DTC

Test value and Test

limit

(GST display)

Description

TID

Unit and

Scaling

EC-534

< FUNCTION DIAGNOSIS >

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ON BOARD DIAGNOSTIC (OBD) SYSTEM

If the ignition switch stays ON after repair work, be sure to turn ignition switch OFF once. Wait at least 10
seconds and then turn it ON (engine stopped) again.

Perform

TM-33, "OBD-II Diagnostic Trouble Code (DTC)"

. (The DTC in TCM will be erased)

Select Service $04 with GST (Generic Scan Tool).

No Tools

NOTE:
If the DTC is not for AT related items (see

EC-919, "DTC Index"

), skip step 2.

If the ignition switch stays ON after repair work, be sure to turn ignition switch OFF once.
Wait at least 10 seconds and then turn it ON (engine stopped) again.

Perform

TM-33, "OBD-II Diagnostic Trouble Code (DTC)"

. (The DTC in the TCM will be erased.)

Change the diagnostic test mode from Mode II to Mode I by depressing the accelerator pedal. Refer to

EC-534, "Malfunction Indicator Lamp (MIL)"

• If the battery is disconnected, the emission-related diagnostic information will be lost within 24

hours.

• The following data are cleared when the ECM memory is erased.
- Diagnostic trouble codes
- 1st trip diagnostic trouble codes
- Freeze frame data
- 1st trip freeze frame data
- System readiness test (SRT) codes
- Test values
Actual work procedures are explained using a DTC as an example. Be careful so that not only the DTC, but all
of the data listed above, are cleared from the ECM memory during work procedures.

Malfunction Indicator Lamp (MIL)

INFOID:0000000001537617

DESCRIPTION

The MIL is located on the instrument panel.

The MIL will light up when the ignition switch is turned ON with-
out the engine running. This is a bulb check.
If the MIL does not light up, refer to

MWI-17

When the engine is started, the MIL should go off.
If the MIL remains on, the on board diagnostic system has
detected an engine system malfunction.

ON BOARD DIAGNOSTIC SYSTEM FUNCTION

The on board diagnostic system has the following three functions.

SEF217U

ON BOARD DIAGNOSTIC (OBD) SYSTEM

EC-535

< FUNCTION DIAGNOSIS >

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When there is an open circuit on MIL circuit, the ECM cannot warn the driver by lighting up MIL when there is
malfunction on engine control system.
Therefore, when electrical controlled throttle and part of ECM related diagnoses are continuously detected as
NG for 5 trips, ECM warns the driver that engine control system malfunctions and MIL circuit is open by means
of operating fail-safe function.
The fail-safe function also operates when above diagnoses except MIL circuit are detected and demands the
driver to repair the malfunction.

MIL Flashing Without DTC

When any SRT codes are not set, MIL may flash without DTC. For the details, refer to

EC-919, "DTC Index"

HOW TO SWITCH DIAGNOSTIC TEST MODE

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.

• Always ECM returns to Diagnostic Test Mode I after ignition switch is turned OFF.

How to Set Diagnostic Test Mode II (Self-diagnostic Results)

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

Repeat the following procedure quickly five times within 5 seconds.

Fully depress the accelerator pedal.

Fully release the accelerator pedal.

Wait 7 seconds, fully depress the accelerator pedal and keep it for approx. 10 seconds until the MIL starts
blinking.
NOTE:
Do not release the accelerator pedal for 10 seconds if MIL may start blinking on the halfway of this
10 seconds. This blinking is displaying SRT status and is continued for another 10 seconds. For
the details, refer to

EC-919, "DTC Index"

Diagnostic Test
Mode

KEY and ENG.
Status

Function

Explanation of Function

Mode I

Ignition switch in
ON position

Engine stopped

BULB CHECK

This function checks the MIL bulb for damage (blown, open
circuit, etc.).
If the MIL does not come on, check MIL circuit.

Engine running

MALFUNCTION
WARNING

This is a usual driving condition. When a malfunction is de-
tected twice in two consecutive driving cycles (two trip de-
tection logic), the MIL will light up to inform the driver that a
malfunction has been detected.
The following malfunctions will light up or blink the MIL in
the 1st trip.
• Misfire (Possible three way catalyst damage)
• One trip detection diagnoses

Mode II

Ignition switch in
ON position

Engine stopped

SELF-DIAGNOSTIC
RESULTS

This function allows DTCs and 1st trip DTCs to be read.

Engine operating condition in fail-safe mode

Engine speed will not rise more than 2,500 rpm due to the fuel cut

EC-536

< FUNCTION DIAGNOSIS >

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ON BOARD DIAGNOSTIC (OBD) SYSTEM

Fully release the accelerator pedal.
ECM has entered to Diagnostic Test Mode II (Self-diagnostic results).
NOTE:
Wait until the same DTC (or 1st trip DTC) appears to confirm all DTCs certainly.

How to Erase Diagnostic Test Mode II (Self-diagnostic Results)

Set ECM in Diagnostic Test Mode II (Self-diagnostic results). Refer to “How to Set Diagnostic Test Mode II
(Self-diagnostic Results)”.

Fully depress the accelerator pedal and keep it for more than 10 seconds.
The emission-related diagnostic information has been erased from the backup memory in the ECM.

Fully release the accelerator pedal, and confirm the DTC 0000 is displayed.

DIAGNOSTIC TEST MODE I — BULB CHECK

In this mode, the MIL on the instrument panel should stay ON. If it remains OFF, check the bulb. Refer to

MWI-

DIAGNOSTIC TEST MODE I — MALFUNCTION WARNING

This DTC number is clarified in Diagnostic Test Mode II (SELF-DIAGNOSTIC RESULTS)

DIAGNOSTIC TEST MODE II — SELF-DIAGNOSTIC RESULTS

In this mode, the DTC and 1st trip DTC are indicated by the number of blinks of the MIL as shown below.
The DTC and 1st trip DTC are displayed at the same time. If the MIL does not illuminate in diagnostic test
mode I (Malfunction warning), all displayed items are 1st trip DTCs. If only one code is displayed when the MIL
illuminates in diagnostic test mode II (SELF-DIAGNOSTIC RESULTS), it is a DTC; if two or more codes are
displayed, they may be either DTCs or 1st trip DTCs. DTC No. is same as that of 1st trip DTC. These uniden-

PBIB0092E

MIL

Condition

When the malfunction is detected.

OFF

No malfunction.

ON BOARD DIAGNOSTIC (OBD) SYSTEM

EC-537

< FUNCTION DIAGNOSIS >

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tified codes can be identified by using the CONSULT-III or GST. A DTC will be used as an example for how to
read a code.

A particular trouble code can be identified by the number of four-digit numeral flashes. The “zero” is indicated
by the number of ten flashes. The “A” is indicated by the number of eleven flash. The length of time the
1,000th-digit numeral flashes on and off is 1.2 seconds consisting of an ON (0.6-second) - OFF (0.6-second)
cycle.
The 100th-digit numeral and lower digit numerals consist of a 0.3-second ON and 0.3-second OFF cycle.
A change from one digit numeral to another occurs at an interval of 1.0-second OFF. In other words, the later
numeral appears on the display 1.3 seconds after the former numeral has disappeared.
A change from one trouble code to another occurs at an interval of 1.8-second OFF.
In this way, all the detected malfunctions are classified by their DTC numbers. The DTC 0000 refers to no mal-
function. (See

EC-919, "DTC Index"

)

How to Erase Diagnostic Test Mode II (Self-diagnostic Results)

The DTC can be erased from the back up memory in the ECM by depressing accelerator pedal. Refer to “How
to Erase Diagnostic Test Mode II (Self-diagnostic Results)”.
• If the battery is disconnected, the DTC will be lost from the backup memory within 24 hours.
• Be careful not to erase the stored memory before starting trouble diagnoses.

OBD System Operation Chart

INFOID:0000000001537618

RELATIONSHIP BETWEEN MIL, 1ST TRIP DTC, DTC, AND DETECTABLE ITEMS

• When a malfunction is detected for the first time, the 1st trip DTC and the 1st trip freeze frame data are

stored in the ECM memory.

• When the same malfunction is detected in two consecutive trips, the DTC and the freeze frame data are

stored in the ECM memory, and the MIL will come on. For details, refer to

EC-521, "Two Trip Detection

Logic"

• The MIL will go off after the vehicle is driven 3 times (driving pattern B) with no malfunction. The drive is

counted only when the recorded driving pattern is met (as stored in the ECM). If another malfunction occurs
while counting, the counter will reset.

• The DTC and the freeze frame data will be stored until the vehicle is driven 40 times (driving pattern A) with-

out the same malfunction recurring (except for Misfire and Fuel Injection System). For Misfire and Fuel Injec-

PBIB3005E

EC-538

< FUNCTION DIAGNOSIS >

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ON BOARD DIAGNOSTIC (OBD) SYSTEM

tion System, the DTC and freeze frame data will be stored until the vehicle is driven 80 times (driving pattern
C) without the same malfunction recurring. The “TIME” in “SELF-DIAGNOSTIC RESULTS” mode of CON-
SULT-III will count the number of times the vehicle is driven.

• The 1st trip DTC is not displayed when the self-diagnosis results in OK for the 2nd trip.

SUMMARY CHART

For details about patterns B and C under “Fuel Injection System” and “Misfire”, see “EXPLANATION FOR DRIVING PATTERNS FOR
“MISFIRE <EXHAUST QUALITY DETERIORATION>”, “FUEL INJECTION SYSTEM”.

For details about patterns A and B under Other, see “EXPLANATION FOR DRIVING PATTERNS FOR “MISFIRE <EXHAUST QUAL-
ITY DETERIORATION>”, “FUEL INJECTION SYSTEM”.

*1: Clear timing is at the moment OK is detected.

*2: Clear timing is when the same malfunction is detected in the 2nd trip.

RELATIONSHIP BETWEEN MIL, DTC, 1ST TRIP DTC AND DRIVING PATTERNS FOR “MISFIRE ”
<EXHAUST QUALITY DETERIORATION>, “FUEL INJECTION SYSTEM”

Items

Fuel Injection System

Misfire

Other

MIL (goes off)

3 (pattern B)

DTC, Freeze Frame Data (no
display)

80 (pattern C)

40 (pattern A)

1st Trip DTC (clear)

1 (pattern C), *

1 (pattern B)

1st Trip Freeze Frame Data
(clear)

*1, *2

1 (pattern B)

ON BOARD DIAGNOSTIC (OBD) SYSTEM

EC-539

< FUNCTION DIAGNOSIS >

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EXPLANATION FOR DRIVING PATTERNS FOR “MISFIRE <EXHAUST QUALITY DETERIORA-
TION>”, “FUEL INJECTION SYSTEM”

Driving pattern B means the vehicle operation as follows:

*1: When the same malfunction is de-

tected in two consecutive trips, MIL
will light up.

*2: MIL will go off after vehicle is driven 3

times (pattern B) without any mal-
functions.

*3: When the same malfunction is de-

tected in two consecutive trips, the
DTC and the freeze frame data will be
stored in ECM.

*4: The DTC and the freeze frame data

will not be displayed any longer after
vehicle is driven 80 times (pattern C)
without the same malfunction. (The
DTC and the freeze frame data still
remain in ECM.)

*5: When a malfunction is detected for

the first time, the 1st trip DTC and the
1st trip freeze frame data will be
stored in ECM.

*6: The 1st trip DTC and the 1st trip

freeze frame data will be cleared at
the moment OK is detected.

*7: When the same malfunction is de-

tected in the 2nd trip, the 1st trip
freeze frame data will be cleared.

*8: 1st trip DTC will be cleared when ve-

hicle is driven once (pattern C) with-
out the same malfunction after DTC
is stored in ECM.

SEF392S

EC-540

< FUNCTION DIAGNOSIS >

[VK56DE]

ON BOARD DIAGNOSTIC (OBD) SYSTEM

All components and systems should be monitored at least once by the OBD system.
• The B counter will be cleared when the malfunction is detected once regardless of the driving pattern.
• The B counter will be counted up when driving pattern B is satisfied without any malfunction.
• The MIL will go off when the B counter reaches 3. (*2 in “OBD SYSTEM OPERATION CHART”)

Driving pattern C means the vehicle operation as follows:
The following conditions should be satisfied at the same time:
Engine speed: (Engine speed in the freeze frame data)

375 rpm

Calculated load value: (Calculated load value in the freeze frame data) x (1

0.1) [%]

Engine coolant temperature (T) condition:
• When the freeze frame data shows lower than 70

C (158

F), T should be lower than 70

C (158

F).

• When the freeze frame data shows higher than or equal to 70

C (158

F), T should be higher than or equal to

C (158

F).

Example:
If the stored freeze frame data is as follows:
Engine speed: 850 rpm, Calculated load value: 30%, Engine coolant temperature: 80

C (176

To be satisfied with driving pattern C, the vehicle should run under the following conditions:
Engine speed: 475 - 1,225 rpm, Calculated load value: 27 - 33%, Engine coolant temperature: more than 70

(158

• The C counter will be cleared when the malfunction is detected regardless of vehicle conditions above.
• The C counter will be counted up when vehicle conditions above is satisfied without the same malfunction.
• The DTC will not be displayed after C counter reaches 80.
• The 1st trip DTC will be cleared when C counter is counted once without the same malfunction after DTC is

stored in ECM.

RELATIONSHIP BETWEEN MIL, DTC, 1ST TRIP DTC AND DRIVING PATTERNS EXCEPT FOR
“MISFIRE <EXHAUST QUALITY DETERIORATION>”, “FUEL INJECTION SYSTEM”

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