2003 NISSAN X-TRAIL engine

EC-880
[YD (WITH EURO-OBD)]
PRECAUTIONS


After performing each TROUBLE DIAGNOSIS, perform DTC
Confirmation Procedure or Overall Function Check.
The DTC should not be displayed in the DTC Confirmation
Procedure if the repair is completed. The Overall Function
Check should be a good result if the repair is completed.

When measuring ECM signals with a circuit tester, never
allow the two tester probes to contact.
Accidental contact of probes will cause a short circuit and
damage the ECM power transistor.

Do not use ECM ground terminals when measuring input/
output voltage. Doing so may result in damage to the ECM's
transistor. Use a ground other than ECM terminals, such as
the ground.

Do not disassemble fuel pump.
If NG, take proper action.

Do not disassemble fuel injector.
If NG, replace fuel injector.

Do not depress accelerator pedal when staring.

Immediately after staring, do not rev up engine unnecessar-
ily.

Do not rev up engine just prior to shutdown.

When installing C.B. ham radio or a mobile phone, be sure
to observe the following as it may adversely affect elec-
tronic control systems depending on installation location.
–Keep the antenna as far as possible from the electronic
control units.
–Keep the antenna feeder line more than 20 cm (8 in) away
from the harness of electronic controls.
Do not let them run parallel for a long distance.
–Adjust the antenna and feeder line so that the standingwave
radio can be kept smaller.
–Be sure to ground the radio to vehicle body.
SAT652J
SEF348N
SEF709Y
SEF708Y

EC-882
[YD (WITH EURO-OBD)]
PREPARATION

PREPARATIONPFP:00002
Special Service ToolsEBS011T9
Commercial Service ToolsEBS011TA
Tool number
Tool nameDescription
EG17650301
Radiator cap tester
adapterAdapting radiator cap tester to radiator cap and
radiator filler neck
a: 28 (1.10) dia.
b: 31.4 (1.236) dia.
c: 41.3 (1.626) dia.
Unit: mm (in)
KV109E0010
Break-out boxMeasuring the ECM signals with a circuit tester
KV109E0080
Y-cable adapterMeasuring the ECM signals with a circuit tester
S-NT564
S-NT825
S-NT826
Tool name Description
Socket wrench Removing and installing engine coolant
temperature sensor
S-NT705

ENGINE CONTROL SYSTEM
EC-883
[YD (WITH EURO-OBD)]
C
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EC

ENGINE CONTROL SYSTEMPFP:23710
System DiagramEBS0116T
PBIB2018E

EC-884
[YD (WITH EURO-OBD)]
ENGINE CONTROL SYSTEM

Vacuum Hose DrawingEBS0116U
Refer to EC-883, "System Diagram" for Vacuum Control System.
PBIB2019E

ENGINE CONTROL SYSTEM
EC-885
[YD (WITH EURO-OBD)]
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EC

System ChartEBS0116V
*1: The input signal is sent to the ECM through CAN communication line.
*2: The output signal is sent from the ECM through CAN communication line.
Fuel Injection Control SystemEBS0116W
SYSTEM DESCRIPTION
Three types of fuel injection control are provided to accommodate engine operating conditions; normal control,
idle control and start control. The ECM determines the appropriate fuel injection control. Under each control,
the amount of fuel injected is adjusted to improve engine performance.
Pulse signals are sent to fuel injectors according to the input signals to adjust the amount of fuel injected to
preset value.
START CONTROL
Input/Output Signal Chart
When the ECM receives a start signal from the ignition switch, the
ECM adapts the fuel injection system for the start control. The
amount of fuel injected at engine starting is a preset program value
in the ECM. The program is determined by the engine speed, engine
coolant temperature and fuel rail pressure.
For better startability under cool engine conditions, the lower the
coolant temperature becomes, the greater the amount of fuel
injected. The ECM ends the start control when the engine speed
reaches the specific value, and shifts the control to the normal or idle
control.
Input (Sensor) ECM Function Output (Actuator)

Accelerator pedal position sensor

Fuel rail pressure sensor

Fuel pump temperature sensor

Engine coolant temperature sensor

Mass air flow sensor

Intake air temperature sensor

Crankshaft position sensor

Camshaft position sensor

Turbocharger boost sensor

Vehicle speed sensor*1

ESP/TCS/ABS control unit*1

Ignition switch

Stop lamp switch

Air conditioner switch*1

Park/neutral position switch

Battery voltage

Fuel level switch

Power steering pressure switch Fuel injection control Fuel injector and Fuel pump
Fuel injection timing control Fuel injector and Fuel pump
Fuel cut control Fuel injector and Fuel pump
Glow control system
Glow relay and glow indicator lamp*
2
On board diagnostic system
Malfunction indicator (MI)*2
EGR volume control EGR volume control valve
Cooling fan control Cooling fan relay
Turbocharger boost controlTurbocharger boost control solenoid
valve
Fuel transport pump control Fuel transport pump relay
Air conditioning cut control Air conditioner relay
Sensor Input Signal to ECM ECM Function Actuator
Engine coolant temperature sensor Engine coolant temperature
Fuel injection
control (start
control)Fuel injector
Fuel pump Crankshaft position sensor Engine speed
Camshaft position sensor Piston position
Ignition switch Start signal
Fuel rail pressure sensor Fuel rail pressure
SEF648S

EC-886
[YD (WITH EURO-OBD)]
ENGINE CONTROL SYSTEM

IDLE CONTROL
Input/Output Signal Chart
*: The input signal is sent to the ECM through CAN communication line.
When the ECM determines that the engine speed is at idle, the fuel injection system is adapted for the idle
control. The ECM regulates the amount of fuel injected corresponding to changes in load applied to the engine
to keep engine speed constant. The ECM also provides the system with a fast idle control in response to the
engine coolant temperature signal.
NORMAL CONTROL
Input/Output Signal Chart
The amount of fuel injected under normal driving conditions is deter-
mined according to sensor signals. The crankshaft position sensor
detects engine speed, the accelerator pedal position sensor detects
accelerator pedal position and fuel rail pressure sensor detects fuel
rail pressure. These sensors send signals to the ECM.
The fuel injection data, predetermined by correlation between vari-
ous engine speeds, accelerator pedal positions and fuel rail pres-
sure are stored in the ECM memory, forming a map. The ECM
determines the optimal amount of fuel to be injected using the sen-
sor signals in comparison with the map.
MAXIMUM AMOUNT CONTROL
Input/Output Signal Chart
The maximum injection amount is controlled to an optimum by the engine speed, intake air amount, engine
coolant temperature, and accelerator opening in accordance with the driving conditions.
This prevents the oversupply of the injection amount caused by decreased air density at a high altitude or dur-
ing a system failure.
Sensor Input Signal to ECM ECM Function Actuator
Engine coolant temperature sensor Engine coolant temperature
Fuel injection
control (Idle
control)Fuel injector
Fuel pump Crankshaft position sensor Engine speed
Battery Battery voltage
Accelerator pedal position sensor Accelerator pedal position
Fuel rail pressure sensor Fuel rail pressure
Vehicle speed sensor* Vehicle speed
Air conditioner switch* Air conditioner signal
Sensor Input Signal to ECM ECM Function Actuator
Crankshaft position sensor Engine speed
Fuel injection
control (Nor-
mal control)Fuel injector
Fuel pump Accelerator pedal position sensor Accelerator position
Fuel rail pressure sensor Fuel rail pressure
SEF649S
Sensor Input Signal to ECM ECM Function Actuator
Mass air flow sensor Amount of intake air
Fuel injection
control (Maxi-
mum amount
control)Fuel Injector Engine coolant temperature sensor Engine coolant temperature
Crankshaft position sensor Engine speed
Accelerator pedal position sensor Accelerator pedal position

ENGINE CONTROL SYSTEM
EC-887
[YD (WITH EURO-OBD)]
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EC

DECELERATION CONTROL
Input/Output Signal Chart
The ECM sends a fuel cut signal to the fuel injectors and fuel pump during deceleration for better fuel effi-
ciency. The ECM determines the time of deceleration according to signals from the accelerator pedal position
sensor and crankshaft position sensor.
Fuel Injection Timing Control SystemEBS0116X
DESCRIPTION
The target fuel injection timing in accordance with the engine speed and the fuel injection amount are recorded
as a map in the ECM beforehand. The ECM determines the optimum injection timing using sensor signals
accordance with the map.
Air Conditioning Cut ControlEBS0116Y
INPUT / OUTPUT SIGNAL CHART
*: The input signal is sent to the ECM through CAN communication line.
SYSTEM DESCRIPTION
This system improves acceleration when the air conditioner is used.
When the accelerator pedal is fully depressed, the air conditioner is turned off for a few seconds.
When engine coolant temperature becomes excessively high, the air conditioner is turned off. This continues
until the engine coolant temperature returns to normal.
Fuel Cut Control (At No Load & High Engine Speed)EBS0116Z
INPUT/OUTPUT SIGNAL CHART
*: The input signal is sent to the ECM through CAN communication line.
If the engine speed is above 2,800 rpm under no load (for example, the shift position is neutral and engine
speed is over 2,800 rpm) fuel will be cut off after some time. The exact time when the fuel is cut off varies
based on engine speed. Fuel cut will be operated until the engine speed reaches 1,500 rpm, then fuel cut will
be cancelled.
NOTE:
This function is different from deceleration control listed under EC-885, "
Fuel Injection Control Sys-
tem" .
Sensor Input Signal to ECM ECM Function Actuator
Accelerator pedal position sensor Accelerator pedal position Fuel injection
control (Decel-
eration control)Fuel injector
Fuel pump
Crankshaft position sensor Engine speed
Sensor Input Signal to ECM ECM Function Actuator
Air conditioner switch* Air conditioner ON signal
Air conditioner
cut controlAir conditioner relay Accelerator pedal position sensor Accelerator pedal opening angle
Vehicle speed sensor* Vehicle speed
Engine coolant temperature sensor Engine coolant temperature
Sensor Input Signal to ECM ECM Function Actuator
Vehicle speed sensor* Vehicle speed
Fuel cut control Fuel injector Accelerator pedal position sensor Accelerator pedal position
Crankshaft position sensor Engine speed

EC-888
[YD (WITH EURO-OBD)]
ENGINE CONTROL SYSTEM

Crankcase Ventilation SystemEBS01170
DESCRIPTION
In this system, blow-by gas is sucked into the air duct after oil separation by oil separator in the rocker cover.
INSPECTION
Ventilation Hose
1. Check hoses and hose connections for leaks.
2. Disconnect all hoses and clean with compressed air. If any hose
cannot be freed of obstructions, replace.
CAN CommunicationEBS01171
SYSTEM DESCRIPTION
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.
PBIB0590E
SEC692