Nissan Pathfinder (2010 year). Manual - part 304

EC-524

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MULTIPORT FUEL INJECTION SYSTEM

FUEL INJECTION TIMING

Two types of systems are used.

Sequential Multiport Fuel Injection System

Fuel is injected into each cylinder during each engine cycle according to the ignition order. This system is used

when the engine is running.

Simultaneous Multiport Fuel Injection System

Fuel is injected simultaneously into all 8 cylinders twice each engine cycle. In other words, pulse signals of the

same width are simultaneously transmitted from the ECM.

The 8 fuel injectors will then receive the signals 2 times for each engine cycle.

This system is used when the engine is being started and/or if the fail-safe system (CPU) is operating.

FUEL SHUT-OFF

Fuel to each cylinder is cut off during deceleration, operation of the engine at excessively high speeds or oper-

ation of the vehicle at excessively high speed.

PBIB0122E

2010 Pathfinder

ELECTRIC IGNITION SYSTEM

EC-525

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ELECTRIC IGNITION SYSTEM

System Description

INFOID:0000000005257500

INPUT/OUTPUT SIGNAL CHART

*1: This signal is sent to the ECM via the CAN communication line.
*2: ECM determines the start signal status by the signals of engine speed and battery voltage.

SYSTEM DESCRIPTION

Ignition order: 1 - 8 - 7 - 3 - 6 - 5 - 4 -2

The ignition timing is controlled by the ECM to maintain the best air-fuel ratio for every running condition of the

engine. The ignition timing data is stored in the ECM.

The ECM receives information such as the injection pulse width and camshaft position sensor signal. Comput-

ing this information, ignition signals are transmitted to the power transistor.

During the following conditions, the ignition timing is revised by the ECM according to the other data stored in

the ECM.

• At starting

• During warm-up

• At  idle

• At low battery voltage

• During acceleration

The knock sensor retard system is designed only for emergencies. The basic ignition timing is programmed

within the anti-knocking zone, if recommended fuel is used under dry conditions. The retard system does not

operate under normal driving conditions. If engine knocking occurs, the knock sensor monitors the condition.

The signal is transmitted to the ECM. The ECM retards the ignition timing to eliminate the knocking condition.

Sensor

Input signal to ECM

ECM function

Actuator

Crankshaft position sensor (POS)

Engine speed*

2

Piston position

Ignition timing 
control

Power transistor

Camshaft position sensor (PHASE)

Mass air flow sensor

Amount of intake air

Engine coolant temperature sensor

Engine coolant temperature

Throttle position sensor

Throttle position

Accelerator pedal position sensor

Accelerator pedal position

Knock sensor

Engine knocking

Battery

Battery voltage*

2

Unified meter control unit

Gear position

Vehicle speed*

1

2010 Pathfinder

EC-526

< FUNCTION DIAGNOSIS >

[VK56DE]

AIR CONDITIONING CUT CONTROL

AIR CONDITIONING CUT CONTROL

Input/Output Signal Chart

INFOID:0000000005257501

*1: This signal is sent to the ECM via the CAN communication line.
*2: ECM determines the start signal status by the signals of engine speed and battery voltage.

System Description

INFOID:0000000005257502

This system improves engine operation when the air conditioner is used.

Under the following conditions, the air conditioner is turned OFF.

• When the accelerator pedal is fully depressed

• When cranking the engine

• At high engine speeds

• When the engine coolant temperature becomes excessively high

• When operating power steering during low engine speed or low vehicle speed

• When engine speed is excessively low

• When refrigerant pressure is excessively low or high

Sensor

Input signal to ECM

ECM function

Actuator

Air conditioner switch

Air conditioner ON signal*

1

Air conditioner 
cut control

Air conditioner relay

Accelerator pedal position sensor

Accelerator pedal position

Crankshaft position sensor (POS)
Camshaft position sensor (PHASE)

Engine speed*

2

Engine coolant temperature sensor

Engine coolant temperature

Battery

Battery voltage*

2

Refrigerant pressure sensor

Refrigerant pressure

Power steering pressure sensor

Power steering operation

Unified meter control unit

Vehicle speed*

1

2010 Pathfinder

AUTOMATIC SPEED CONTROL DEVICE (ASCD)

EC-527

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AUTOMATIC SPEED CONTROL DEVICE (ASCD)

System Description

INFOID:0000000005257503

INPUT/OUTPUT SIGNAL CHART

*: This signal is sent to the ECM via the CAN communication line

BASIC ASCD SYSTEM

Refer to Owner's Manual for ASCD operating instructions.

Automatic Speed Control Device (ASCD) allows a driver to keep vehicle at predetermined constant speed

without depressing accelerator pedal. Driver can set vehicle speed in advance between approximately 40 km/

h (25 MPH) and 144 km/h (89 MPH).

ECM controls throttle angle of electric throttle control actuator to regulate engine speed.

Operation status of ASCD is indicated by CRUISE indicator and SET indicator on combination meter. If any

malfunction occurs in ASCD system, CRUISE indicator blinks and ASCD control is deactivated.

NOTE:

Always drive vehicle in a safe manner according to traffic conditions and obey all traffic laws.

SET OPERATION

Press MAIN switch. (The CRUISE indicator on combination meter illuminates.)

When vehicle speed reaches a desired speed between approximately 40 km/h (25 MPH) and 144 km/h (89

MPH), press SET/COAST switch. (Then SET indicator on combination meter illuminates.)

ACCELERATE OPERATION

If the RESUME/ACCELERATE switch is pressed during cruise control driving, increase the vehicle speed until

the switch is released or vehicle speed reaches maximum speed controlled by the system.

And then ASCD will maintain the new set speed.

CANCEL OPERATION

When any of following conditions exist, cruise operation will be canceled.

• CANCEL switch is pressed

• More than 2 switches at ASCD steering switch are pressed at the same time (Set speed will be cleared)

• Brake pedal is depressed

• Selector lever position is changed to N, P, R position

• Vehicle speed decreased to 13 km/h (8 MPH) lower than the set speed

• VDC system is operated

When the ECM detects any of the following conditions, the ECM will cancel the cruise operation and inform

the driver by blinking CRUISE indicator.

• Engine coolant temperature is slightly higher than the normal operating temperature, CRUISE indicator may

blink slowly.

When the engine coolant temperature decreases to the normal operating temperature, CRUISE indicator will

stop blinking and the cruise operation will be able to work by pressing SET/COAST switch or RESUME/

ACCELERATE switch.

• Malfunction for some self-diagnoses regarding ASCD control: SET indicator will blink quickly.

If MAIN switch is turned to OFF while ASCD is activated, all of ASCD operations will be canceled and vehicle

speed memory will be erased.

COAST OPERATION

When the SET/COAST switch is pressed during cruise control driving, decrease vehicle set speed until the

switch is released. And then ASCD will maintain the new set speed.

RESUME OPERATION

Sensor

Input signal to ECM

ECM function

Actuator

ASCD brake switch

Brake pedal operation

ASCD vehicle speed control

Electric throttle control 
actuator

Stop lamp switch

Brake pedal operation

ASCD steering switch

ASCD steering switch operation

Unified meter control unit

Gear position

Vehicle speed*

TCM

Powertrain revolution*

2010 Pathfinder

EC-528

< FUNCTION DIAGNOSIS >

[VK56DE]

AUTOMATIC SPEED CONTROL DEVICE (ASCD)

When the RESUME/ACCELERATE switch is pressed after canceling operation other than pressing MAIN

switch, vehicle speed will return to last set speed. To resume vehicle set speed, vehicle condition must meet

following conditions.

• Brake pedal is released

• A/T selector lever position is other than P and N

• Vehicle speed is greater than 40 km/h (25 MPH) and less than 144 km/h (89 MPH)

Component Description

INFOID:0000000005257504

ASCD STEERING SWITCH

Refer to 

EC-823, "Component Description"

.

ASCD BRAKE SWITCH

Refer to 

EC-827, "Component Description"

.

STOP LAMP SWITCH

Refer to 

EC-832, "Description"

.

ELECTRIC THROTTLE CONTROL ACTUATOR 

Refer to 

EC-838, "Description"

.

ASCD INDICATOR

Refer to 

EC-870, "Component Description"

.

2010 Pathfinder

CAN COMMUNICATION

EC-529

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CAN COMMUNICATION

System Description

INFOID:0000000005257505

CAN (Controller Area Network) is a serial communication line for real time application. It is an on-vehicle mul-

tiplex communication line with high data communication speed and excellent error detection ability. Many elec-

tronic control units are equipped onto a vehicle, and each control unit shares information and links with other

control units during operation (not independent). In CAN communication, control units are connected with 2

communication lines (CAN H line, CAN L line) allowing a high rate of information transmission with less wiring.

Each control unit transmits/receives data but selectively reads required data only.

Refer to 

LAN-53, "CAN Communication Signal Chart"

, about CAN communication for detail.

2010 Pathfinder

EC-530

< FUNCTION DIAGNOSIS >

[VK56DE]

COOLING FAN CONTROL

COOLING FAN CONTROL

Description

INFOID:0000000005257506

SYSTEM DESCRIPTION

Cooling Fan Control

*1: The ECM determines the start signal status by the signals of engine speed and battery voltage.
*2: This signal is sent to ECM via the CAN communication line.

The ECM controls the cooling fan speed corresponding to the vehicle speed, engine coolant temperature,

refrigerant pressure and air conditioner ON signal. The control system has a 3-step control [HIGH/LOW/OFF].

Cooling Fan Operation

Cooling Fan Relay Operation

The ECM controls cooling fan relays in the IPDM E/R via the CAN communication line.

Sensor

Input Signal to ECM

ECM function

Actuator

Crankshaft position sensor (POS)
Camshaft position sensor (PHASE)

Engine speed*

1

Cooling fan 
control

IPDM E/R
(Cooling fan relays)

Battery

Battery voltage*

1

Unified meter control unit

Vehicle speed*

2

Engine coolant temperature sensor

Engine coolant temperature

Air conditioner switch

Air conditioner ON signal*

2

Refrigerant pressure sensor

Refrigerant pressure

JMBIA0700GB

Cooling fan speed

Cooling fan relay

LO

HI

Stop (OFF)

OFF

OFF

Low (LOW)

ON

OFF

High (HI)

ON

ON

2010 Pathfinder

EVAPORATIVE EMISSION SYSTEM

EC-531

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EVAPORATIVE EMISSION SYSTEM

Description

INFOID:0000000005257507

SYSTEM DESCRIPTION

The evaporative emission system is used to reduce hydrocarbons emitted into the atmosphere from the fuel

system. This reduction of hydrocarbons is accomplished by activated charcoals in the EVAP canister.

The fuel vapor in the sealed fuel tank is led into the EVAP canister which contains activated carbon and the

vapor is stored there when the engine is not operating or when refueling to the fuel tank.

The vapor in the EVAP canister is purged by the air through the purge line to the intake manifold when the

engine is operating. EVAP canister purge volume control solenoid valve is controlled by ECM. When the

engine operates, the flow rate of vapor controlled by EVAP canister purge volume control solenoid valve is

proportionally regulated as the air flow increases.

EVAP canister purge volume control solenoid valve also shuts off the vapor purge line during decelerating and

idling.

PBIB3639E

2010 Pathfinder