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Nissan Pathfinder (2012 year). Manual - part 250

DIAGNOSIS SYSTEM (ECM)

EC-81

< SYSTEM DESCRIPTION >

[VQ40DE]

MASS AIRFLOW

g/s

• Indicates the mass air flow computed by ECM ac-

cording to the signal voltage of the mass air flow
sensor.

PURG VOL C/V

• Indicates the EVAP canister purge volume control

solenoid valve control value computed by the ECM
according to the input signals.

• The opening becomes larger as the value increas-

es.

INT/V TIM(B1)

• Indicates [

CA] of intake camshaft advanced angle.

INT/V TIM(B2)

INT/V SOL(B1)

• The control condition of the intake valve timing con-

trol solenoid valve (determined by ECM according
to the input signals) is indicated.

• The advance angle becomes larger as the value in-

creases.

INT/V SOL(B2)

VIAS S/V-1

ON/OFF

• The control condition of the VIAS control solenoid

valve (determined by ECM according to the input
signals) is indicated.
ON: VIAS control solenoid valve is operating.
OFF: VIAS control solenoid valve is not operating.

AIR COND RLY

ON/OFF

• The air conditioner relay control condition (deter-

mined by ECM according to the input signals) is in-
dicated.

FUEL PUMP RLY

ON/OFF

• Indicates the fuel pump relay control condition de-

termined by ECM according to the input signals.

VENT CONT/V

ON/OFF

• The control condition of the EVAP canister vent

control valve (determined by ECM according to the
input signals) is indicated.
ON: Closed
OFF: Open

THRTL RELAY

ON/OFF

• Indicates the throttle control motor relay control

condition determined by the ECM according to the
input signals.

COOLING FAN

HI/LOW/

OFF

• The control condition of the cooling fan (deter-

mined by ECM according to the input signals) is in-
dicated.
HI: High speed operation
LOW: Low speed operation
OFF: Stop

HO2S2 HTR (B1)

ON/OFF • Indicates [ON/OFF] condition of heated oxygen

sensor 2 heater determined by ECM according to
the input signals.

HO2S2 HTR (B2)

ON/OFF

I/P PULLY SPD

rpm

• Indicates the engine speed computed from thein-

put speed sensor signal.

VEHICLE SPEED

km/h or

mph

• Indicates the vehicle speed computed from the out-

put speed sensor signal.

IDL A/V LEARN

YET/

CMPLT

• Displays the condition of idle air volume learning

YET: Idle air volume learning has not been per-
formed yet.
CMPLT: Idle air volume learning has already been
performed successfully.

TRVL AFTER MIL

km or

mile

• Distance traveled while MIL is activated.

A/F S1 HTR(B1)

• Air fuel ratio (A/F) sensor 1 heater control value

computed by ECM according to the input signals.

• The current flow to the heater becomes larger as

the value increases.

A/F S1 HTR(B2)

Monitored item

Unit

Description

Remarks

August 2012

2012 Pathfinder

EC-82

< SYSTEM DESCRIPTION >

[VQ40DE]

DIAGNOSIS SYSTEM (ECM)

AC PRESS SEN

• The signal voltage from the refrigerant pressure

sensor is displayed.

VHCL SPEED SE

km/h or

mph

• The vehicle speed computed from the vehicle

speed signal sent from TCM is displayed.

SET VHCL SPD

km/h or

mph

• The preset vehicle speed is displayed.

MAIN SW

ON/OFF

• Indicates [ON/OFF] condition from MAIN switch

signal.

CANCEL SW

ON/OFF

• Indicates [ON/OFF] condition from CANCEL switch

signal.

RESUME/ACC SW

ON/OFF

• Indicates [ON/OFF] condition from RESUME/AC-

CELERATE switch signal.

SET SW

ON/OFF

• Indicates [ON/OFF] condition from SET/COAST

switch signal.

BRAKE SW1

ON/OFF

• Indicates [ON/OFF] condition from ASCD brake

switch signal.

BRAKE SW2

ON/OFF

• Indicates [ON/OFF] condition of stop lamp switch

signal.

VHCL SPD CUT

NON/

CUT

• Indicates the vehicle cruise condition.

NON: Vehicle speed is maintained at the ASCD set
speed.
CUT: Vehicle speed increased to excessively high
compared with the ASCD set speed, and ASCD op-
eration is cut off.

LO SPEED CUT

NON/

CUT

• Indicates the vehicle cruise condition.

NON: Vehicle speed is maintained at the ASCD set
speed.
CUT: Vehicle speed decreased to excessively low
compared with the ASCD set speed, and ASCD op-
eration is cut off.

AT OD MONITOR

ON/OFF

• Indicates [ON/OFF] condition of A/T O/D according

to the input signal from the TCM.

AT OD CANCEL

ON/OFF

• Indicates [ON/OFF] condition of A/T O/D cancel

signal sent from the TCM.

CRUISE LAMP

ON/OFF

• Indicates [ON/OFF] condition of CRUISE lamp de-

termined by the ECM according to the input sig-
nals.

SET LAMP

ON/OFF

• Indicates [ON/OFF] condition of SET lamp deter-

mined by the ECM according to the input signals.

ALT DUTY

• Indicates the duty ratio of the power generation

command value. The ratio is calculated by ECM
based on the battery current sensor signal.

BAT CUR SEN

• The signal voltage of battery current sensor is dis-

played.

ALT DUTY SIG

ON/OFF

• The control condition of the power generation volt-

age variable control (determined by ECM accord-
ing to the input signals) is indicated.
ON: Power generation voltage variable control is
active
OFF: Power generation voltage variable control is
inactive.

A/F ADJ-B1

—

• Indicates the correction factor saved in ECM. The

factor is calculated from the difference between the
target air-fuel ratio saved in ECM and the air-fuel
ratio calculated from A/F sensor 1 signal.

A/F ADJ-B2

—

Monitored item

Unit

Description

Remarks

August 2012

2012 Pathfinder

DIAGNOSIS SYSTEM (ECM)

EC-83

< SYSTEM DESCRIPTION >

[VQ40DE]

*: The item is indicated, but not used.

NOTE:

Any monitored item that does not match the vehicle being diagnosed is deleted from the display automatically.

ACTIVE TEST MODE

Test Item

EVAP LEAK DIAG

YET/

CMPLT

• Indicates the condition of EVAP leak diagnosis.

YET: EVAP leak diagnosis has not been performed
yet.
CMPLT: EVAP leak diagnosis has been performed
successfully.

EVAP DIAG READY

ON/OFF

• Indicates the ready condition of EVAP leak diagno-

sis.
ON: Diagnosis has been ready condition.
OFF: Diagnosis has not been ready condition.

HO2 S2 DIAG1(B1)

INCMP/

CMPLT

• Indicates DTC P0139 self-diagnosis (delayed re-

sponce) condition.
INCMP: Self-diagnosis is incomplete.
CMPLT: Self-diagnosis is complete.

HO2 S2 DIAG1(B2)

INCMP/

CMPLT

• Indicates DTC P0159 self-diagnosis (delayed re-

sponce) condition.
INCMP: Self-diagnosis is incomplete.
CMPLT: Self-diagnosis is complete.

HO2 S2 DIAG2(B1)

INCMP/

CMPLT

• Indicates DTC P0139 self-diagnosis (slow re-

sponce) condition.
INCMP: Self-diagnosis is incomplete.
CMPLT: Self-diagnosis is complete.

HO2 S2 DIAG2(B2)

INCMP/

CMPLT

• Indicates DTC P0159 self-diagnosis (slow re-

sponce) condition.
INCMP: Self-diagnosis is incomplete.
CMPLT: Self-diagnosis is complete.

THRTL STK CNT B1

—

Monitored item

Unit

Description

Remarks

TEST ITEM

CONDITION

JUDGEMENT

CHECK ITEM (REMEDY)

FUEL INJEC-
TION

• Engine: Return to the original

non-standard condition

• Change the amount of fuel injec-

tion using CONSULT.

If malfunctioning symptom disap-
pears, see CHECK ITEM.

• Harness and connectors
• Fuel injector
• Air fuel ratio (A/F) sensor 1

IGNITION TIM-
ING

• Engine: Return to the original

non-standard condition

• Timing light: Set
• Retard the ignition timing using

CONSULT.

If malfunctioning symptom disap-
pears, see CHECK ITEM.

• Perform Idle Air Volume Learning.

POWER BAL-
ANCE

• Engine: After warming up, idle the

engine.

• A/C switch: OFF
• Shift lever: P or N
• Cut off each fuel injector signal

one at a time using CONSULT.

Engine runs rough or stops.

• Harness and connectors
• Compression
• Fuel injector
• Power transistor
• Spark plug
• Ignition coil

COOLING FAN*

• Ignition switch: ON
• Turn the cooling fan HI, LOW and

OFF using CONSULT.

Cooling fan moves and stops.

• Harness and connectors
• Cooling fan motor
• IPDM E/R

ENG COOLANT
TEMP

• Engine: Return to the original

non-standard condition

• Change the engine coolant tem-

perature using CONSULT.

If malfunctioning symptom disap-
pears, see CHECK ITEM.

• Harness and connectors
• Engine coolant temperature sen-

sor

• Fuel injector

August 2012

2012 Pathfinder

EC-84

< SYSTEM DESCRIPTION >

[VQ40DE]

DIAGNOSIS SYSTEM (ECM)

*: Leaving cooling fan OFF with CONSULT while engine is running may cause the engine to overheat.

DTC & SRT CONFIRMATION MODE

SRT STATUS Mode

• For items whose SRT codes are set, “CMPLT” is displayed on the CONSULT screen; for items whose SRT

codes are not set, “INCMP” is displayed.

• “SRT STATUS” provides the presence or absence of permanent DTCs stored in ECM memory.

PERMANENT DTC STATUS Mode

How to display permanent DTC status

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.

4. Turn ignition switch ON.

5. Select “PERMANENT DTC STATUS” in “DTC & SRT CONFIRMATION” mode with CONSULT.

NOTE:

Permanent DTCs stored in ECM memory are displayed on the CONSULT screen to show if a driving pat-

tern required for erasing permanent DTCs is complete (CMPLT) or incomplete (INCMP).

CAUTION:

FUEL PUMP RE-
LAY

• Ignition switch: ON (Engine

stopped)

• Turn the fuel pump relay ON and

OFF using CONSULT and listen
to operating sound.

Fuel pump relay makes the operat-
ing sound.

• Harness and connectors
• Fuel pump relay

VIAS S/V-1

• Ignition switch: ON
• Turn solenoid valve ON and OFF

with CONSULT and listen for op-
erating sound.

Solenoid valve makes an operating
sound.

• Harness and connectors
• Solenoid valve

PURG VOL
CONT/V

• Engine: After warming up, run en-

gine at 1,500 rpm.

• Change the EVAP canister purge

volume control solenoid valve
opening percent using CON-
SULT.

Engine speed changes according to
the opening percent.

• Harness and connectors
• Solenoid valve

FUEL/T TEMP
SEN

• Change the fuel tank temperature using CONSULT.

VENT CON-
TROL/V

• Ignition switch: ON (Engine

stopped)

• Turn solenoid valve ON and OFF

with the CONSULT and listen to
operating sound.

Solenoid valve makes an operating
sound.

• Harness and connectors
• Solenoid valve

V/T ASSIGN AN-
GLE

• Engine: Return to the original

non-standard condition

• Change intake valve timing using

CONSULT.

If malfunctioning symptom disap-
pears, see CHECK ITEM.

• Harness and connectors
• Intake valve timing control sole-

noid valve

ALTERNATOR
DUTY

• Engine: Idle
• Change duty ratio using CON-

SULT.

Battery voltage changes.

• Harness and connectors
• IPDM E/R
• Alternator

TEST ITEM

CONDITION

JUDGEMENT

CHECK ITEM (REMEDY)

August 2012

2012 Pathfinder

DIAGNOSIS SYSTEM (ECM)

EC-85

< SYSTEM DESCRIPTION >

[VQ40DE]

Since the “PERMANENT DTC STATUS” screen displays the previous trip information, repeat the

following twice to update the information: “Ignition switch OFF”, “Wait for more than 10 seconds”

and “Ignition switch ON”.

NOTE:

This mode is not used in regions that permanent DTCs are not regulated by law.

SRT WORK SUPPORT Mode

This mode enables a technician to drive a vehicle to set the SRT while monitoring the SRT status.

PERMANENT DTC WORK SUPPORT Mode

This mode enables a technician to drive a vehicle to complete the driving pattern that is reguired for erasing

permanent DTC.

NOTE:

This mode is not used in regions that permanent DTCs are not regulated by law.

DTC WORK SUPPORT Mode

*: DTC P1456 does not apply to R51 models but appears in DTC Work Support Mode screens.

JSBIA0062GB

Test mode

Test item

Corresponding DTC No.

Reference page

EVAPORATIVE SYS-
TEM

EVP V/S LEAK P0456/P1456*

P0442

EC-237

P0455

EC-275

P0456

EC-282

PURG VOL CN/V P1444

P0443

EC-244

PURG FLOW P0441

P0441

EC-232

A/F SEN1

A/F SEN1(B1) P1278/P1279

P0133

EC-160

A/F SEN1(B1) P1276

P0130

EC-148

A/F SEN1(B2) P1288/P1289

P0153

EC-160

A/F SEN1(B2) P1286

P0150

EC-148

HO2S2

HO2S2 (B1) P1146

P0138

EC-171

HO2S2(B1) P1147

P0137

EC-165

HO2S2(B1) P0139

P0139

EC-179

HO2S2(B2) P1166

P0158

EC-171

HO2S2(B2) P1167

P0157

EC-165

HO2S2(B2) P0159

P0159

EC-179

August 2012

2012 Pathfinder

EC-86

< DTC/CIRCUIT DIAGNOSIS >

[VQ40DE]

TROUBLE DIAGNOSIS - SPECIFICATION VALUE

DTC/CIRCUIT DIAGNOSIS

TROUBLE DIAGNOSIS - SPECIFICATION VALUE

Description

INFOID:0000000007357982

The specification (SP) value indicates the tolerance of the value that is displayed in “SPEC” of “DATA MONI-

TOR” mode of CONSULT during normal operation of the Engine Control System. When the value in “SPEC” of

“DATA MONITOR” mode is within the SP value, the Engine Control System is confirmed OK. When the value

“SPEC” of “DATA MONITOR” mode is NOT within the SP value, the Engine Control System may have one or

more malfunctions.

The SP value is used to detect malfunctions that may affect the Engine Control System, but will not illuminate

the MIL.

The SP value will be displayed for the following three items:

• B/FUEL SCHDL (The fuel injection pulse width programmed into ECM prior to any learned on board correc-

tion)

• A/F ALPHA-B1/B2 (The mean value of air-fuel ratio feedback correction factor per cycle)

• MAS A/F SE-B1 (The signal voltage of the mass air flow sensor)

Testing Condition

INFOID:0000000007357983

• Vehicle driven distance: More than 5,000 km (3,107 miles)
• Barometric pressure: 98.3 - 104.3 kPa (1.003 - 1.064 kg/cm

, 14.25 - 15.12 psi)

• Atmospheric temperature: 20 - 30

C (68 - 86

• Engine coolant temperature: 75 - 95

C (167 - 203

• Transmission: Warmed-up*

• Electrical load: Not applied*

• Engine speed: Idle

*1: After the engine is warmed up to normal operating temperature, drive vehicle until “FLUID TEMP SE” (A/T

fluid temperature sensor signal) indicates more than 60

C (140

F).

*2: Rear window defogger switch, air conditioner switch lighting switch are OFF. Steering wheel is straight

ahead.

Inspection Procedure

INFOID:0000000007357984

NOTE:

Perform “SPEC” of “DATA MONITOR” mode in maximum scale display.
1. Perform

EC-20, "Basic Inspection"

2. Confirm that the testing conditions indicated above are met.
3. Select “B/FUEL SCHDL”, “A/F ALPHA-B1”, “A/F ALPHA-B2” and “MAS A/F SE-B1” in “SPEC” of “DATA

MONITOR” mode with CONSULT.

4. Make sure that monitor items are within the SP value.
5. If NG, go to

EC-86, "Diagnosis Procedure"

Diagnosis Procedure

INFOID:0000000007357985

OVERALL SEQUENCE

August 2012

2012 Pathfinder