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Nissan Pathfinder (2008 year). Manual - part 304

ON BOARD DIAGNOSTIC (OBD) SYSTEM

EC-549

< FUNCTION DIAGNOSIS >

[VK56DE]

A/F S1 HTR (B1)
[%]

• A/F sensor 1 heater control value com-

puted by ECM according to the input sig-
nals.

• The current flow to the heater becomes

larger as the value increases.

A/F S1 HTR (B2)
[%]

AC PRESS SEN [V]

• 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 combina-
tion meter 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 CAN-

CEL switch signal.

RESUME/ACC SW
[ON/OFF]

• Indicates [ON/OFF] condition from RE-

SUME/ACCELERATE 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 exces-
sively high compared with the ASCD set
speed, and ASCD operation 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 exces-
sively low compared with the ASCD set
speed, and ASCD operation 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 determined by the ECM according
to the input signals.

SET LAMP
[ON/OFF]

• Indicates [ON/OFF] condition of SET

lamp determined by the ECM according
to the input signals.

ALT DUTY [%]

• Indicates the duty ratio of the power gen-

eration command value. The ratio is cal-
culated by ECM based on the battery
current sensor signal.

BAT CUR SEN
[mV]

• The signal voltage of battery current sen-

sor is displayed.

Monitored item

[Unit]

ECM IN-

PUT SIG-

NALS

MAIN

SIGNALS

Description

Remarks

EC-550

< FUNCTION DIAGNOSIS >

[VK56DE]

ON BOARD DIAGNOSTIC (OBD) SYSTEM

NOTE:

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

ACTIVE TEST MODE

Test Item

ALT DUTY SIG
[ON/OFF]

• The control condition of the power gener-

ation voltage variable control (deter-
mined by ECM according 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 stored in

ECM. The factor is calculated from the
difference between the target air/fuel ra-
tio stored in ECM and the air-fuel ratio
calculated from air fuel ratio (A/F) sensor
1 signal.

A/F ADJ-B2

Voltage [V]

• Voltage, frequency, duty cycle or pulse

width measured by the probe.

Frequency [msec],
[Hz] or [%]

DUTY-HI

DUTY-LOW

PLS WIDTH-HI

PLS WIDTH-LOW

Monitored item

[Unit]

ECM IN-

PUT SIG-

NALS

MAIN

SIGNALS

Description

Remarks

TEST ITEM

CONDITION

JUDGEMENT

CHECK ITEM (REMEDY)

FUEL INJEC-
TION

• Engine: Return to the original

trouble condition

• Change the amount of fuel injec-

tion using CONSULT-III.

If trouble symptom disappears, see
CHECK ITEM.

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

IGNITION TIM-
ING

• Engine: Return to the original

trouble condition

• Timing light: Set
• Retard the ignition timing using

CONSULT-III.

If trouble symptom disappears, see
CHECK ITEM.

• Perform Idle Air Volume Learning.

POWER BAL-
ANCE

• Engine: After warming up, idle the

engine.

• A/C switch: OFF
• Selector lever: P or N
• Cut off each injector signal one at

a time using CONSULT-III.

Engine runs rough or dies.

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

COOLING FAN*

• Ignition switch: ON
• Turn the cooling fan HI and OFF

using CONSULT-III.

Cooling fan moves and stops.

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

ENG COOLANT
TEMP

• Engine: Return to the original

trouble condition

• Change the engine coolant tem-

perature using CONSULT-III.

If trouble symptom disappears, see
CHECK ITEM.

• Harness and connectors
• Engine coolant temperature sen-

sor

• Fuel injector

FUEL PUMP RE-
LAY

• Ignition switch: ON

(Engine stopped)

• Turn the fuel pump relay ON and

OFF using CONSULT-III and lis-
ten to operating sound.

Fuel pump relay makes the operat-
ing sound.

• Harness and connectors
• Fuel pump relay

ON BOARD DIAGNOSTIC (OBD) SYSTEM

EC-551

< FUNCTION DIAGNOSIS >

[VK56DE]

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

DTC & SRT CONFIRMATION MODE

SRT STATUS Mode

For details, refer to

EC-919, "DTC Index"

SRT WORK SUPPORT Mode

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

DTC WORK SUPPORT Mode

*: DTC P1442 and P1456 does not apply to R51 models but appears in DTC Work Support Mode screens.

Generic Scan Tool (GST) Function

INFOID:0000000001537620

DESCRIPTION

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-III.

Engine speed changes according to
the opening percent.

• Harness and connectors
• Solenoid valve

FUEL/T TEMP
SEN

• Change the fuel tank temperature using CONSULT-III.

VENT CON-
TROL/V

• Ignition switch: ON

(Engine stopped)

• Turn solenoid valve ON and OFF

with the CONSULT-III 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

trouble condition

• Change intake valve timing using

CONSULT-III.

If trouble symptom disappears, see
CHECK ITEM.

• Harness and connectors
• Intake valve timing control sole-

noid valve

ALTERNATOR
DUTY

• Engine: Idle
• Change duty ratio using CON-

SULT-III.

Battery voltage changes.

• Harness and connectors
• IPDM E/R
• Alternator

TEST ITEM

CONDITION

JUDGEMENT

CHECK ITEM (REMEDY)

Test mode

Test item

Corresponding DTC No.

Reference page

EVAPORATIVE
SYSTEM

PURG FLOW P0441

P0441

EC-694

EVP SML LEAK P0442/P1442*

P0442

EC-699

P0455

EC-736

EVP V/S LEAK P0456/P1456*

P0456

EC-743

PURG VOL CN/V P1444

P0443

EC-707

A/F SEN1

A/F SEN1 (B1) P1276

P0130

EC-615

A/F SEN1 (B1) P1278/P1279

P0133

EC-627

A/F SEN1 (B2) P1286

P0150

EC-615

A/F SEN1 (B2) P1288/P1289

P0153

EC-627

HO2S2

HO2S2 (B1) P0139

P0139

EC-646

HO2S2 (B1) P1146

P0138

EC-638

HO2S2 (B1) P1147

P0137

EC-633

HO2S2 (B2) P0159

P0159

EC-646

HO2S2 (B2) P1166

P0158

EC-638

HO2S2 (B2) P1167

P0157

EC-633

EC-552

< FUNCTION DIAGNOSIS >

[VK56DE]

ON BOARD DIAGNOSTIC (OBD) SYSTEM

Generic Scan Tool (OBDII scan tool) complying with SAE J1978 has
8 different functions explained below.
ISO15765-4 is used as the protocol.
The name GST or Generic Scan Tool is used in this service manual.

FUNCTION

INSPECTION PROCEDURE

Turn ignition switch OFF.

Connect GST to data link connector (1), which is located under
LH dash panel near the hood opener handle.

SEF139P

Diagnostic test mode

Function

Service $01

READINESS TESTS

This diagnostic service gains access to current emission-related data values, including an-
alog inputs and outputs, digital inputs and outputs, and system status information.

Service $02

(FREEZE DATA)

This diagnostic service gains access to emission-related data value which were stored by
ECM during the freeze frame. For details, refer to

EC-919, "DTC Index"

Service $03

DTCs

This diagnostic service gains access to emission-related power train trouble codes which
were stored by ECM.

Service $04

CLEAR DIAG INFO

This diagnostic service can clear all emission-related diagnostic information. This in-
cludes:
• Clear number of diagnostic trouble codes (Service $01)
• Clear diagnostic trouble codes (Service $03)
• Clear trouble code for freeze frame data (Service $01)
• Clear freeze frame data (Service $02)
• Reset status of system monitoring test (Service $01)
• Clear on board monitoring test results (Service $06 and $07)

Service $06

(ON BOARD TESTS)

This diagnostic service accesses the results of on board diagnostic monitoring tests of
specific components/systems that are not continuously monitored.

Service $07

(ON BOARD TESTS)

This diagnostic service enables the off board test drive to obtain test results for emission-
related powertrain components/systems that are continuously monitored during normal
driving conditions.

Service $08

—

This diagnostic service can close EVAP system in ignition switch ON position (Engine
stopped). When this diagnostic service is performed, the EVAP canister vent control valve
can be closed.
In the following conditions, this diagnostic service cannot function.
• Low ambient temperature
• Low battery voltage
• Engine running
• Ignition switch OFF
• Low fuel temperature
• Too much pressure is applied to EVAP system

Service $09

(CALIBRATION ID)

This diagnostic service enables the off-board test device to request specific vehicle infor-
mation such as Vehicle Identification Number (VIN) and Calibration IDs.

(2)

Brake pedal

ALBIA0359ZZ

ON BOARD DIAGNOSTIC (OBD) SYSTEM

EC-553

< FUNCTION DIAGNOSIS >

[VK56DE]

Turn ignition switch ON.

Enter the program according to instruction on the screen or in
the operation manual.
(*: Regarding GST screens in this section, sample screens are
shown.)

Perform each diagnostic service according to each service pro-
cedure.
For further information, see the GST Operation Manual of
the tool maker.

SEF398S

SEF416S

EC-554

< COMPONENT DIAGNOSIS >

[VK56DE]

TROUBLE DIAGNOSIS - SPECIFICATION VALUE

COMPONENT DIAGNOSIS

TROUBLE DIAGNOSIS - SPECIFICATION VALUE

Description

INFOID:0000000001537621

The specification (SP) value indicates the tolerance of the value that is displayed in “SPEC” of “DATA MONI-
TOR” mode with CONSULT-III 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 in “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 light 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:0000000001537622

• 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

• Engine speed: Idle
• Transmission: Warmed-up
- After the engine is warmed up to normal operating temperature, drive vehicle until “ATF TEMP SE 1” (A/T

fluid temperature sensor signal) indicates more than 60

C (140

F).

• Electrical load: Not applied
- Rear window defogger switch, air conditioner switch, lighting switch are OFF. Steering wheel is straight

ahead.

Inspection Procedure

INFOID:0000000001537623

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

Perform

EC-492, "Basic Inspection"

Confirm that the testing conditions indicated above are met.

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-III.