2003 NISSAN X-TRAIL width

EC-498
[QR (WITHOUT EURO-OBD)]
ENGINE CONTROL SYSTEM

MIXTURE RATIO SELF-LEARNING CONTROL
The mixture ratio feedback control system monitors the mixture ratio signal transmitted from heated oxygen
sensor 1. This feedback signal is then sent to the ECM. The ECM controls the basic mixture ratio as close to
the theoretical mixture ratio as possible. However, the basic mixture ratio is not necessarily controlled as orig-
inally designed. Both manufacturing differences (i.e., mass air flow sensor hot wire) and characteristic
changes during operation (i.e., injector clogging) directly affect mixture ratio.
Accordingly, the difference between the basic and theoretical mixture ratios is monitored in this system. This is
then computed in terms of “injection pulse duration” to automatically compensate for the difference between
the two ratios.
“Fuel trim” refers to the feedback compensation value compared against the basic injection duration. Fuel trim
includes short term fuel trim and long term fuel trim.
“Short term fuel trim” is the short-term fuel compensation used to maintain the mixture ratio at its theoretical
value. The signal from heated oxygen sensor 1 indicates whether the mixture ratio is RICH or LEAN compared
to the theoretical value. The signal then triggers a reduction in fuel volume if the mixture ratio is rich, and an
increase in fuel volume if it is lean.
“Long term fuel trim” is overall fuel compensation carried out long-term to compensate for continual deviation
of the short term fuel trim from the central value. Such deviation will occur due to individual engine differences,
wear over time and changes in the usage environment.
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 firing order. This system is used
when the engine is running.
Simultaneous Multiport Fuel Injection System
Fuel is injected simultaneously into all four cylinders twice each engine cycle. In other words, pulse signals of
the same width are simultaneously transmitted from the ECM.
The four injectors will then receive the signals two 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 or operation of the engine at excessively high speeds.
SEF337W

ENGINE CONTROL SYSTEM
EC-499
[QR (WITHOUT EURO-OBD)]
C
D
E
F
G
H
I
J
K
L
MA
EC

Electronic Ignition (EI) SystemEBS010WQ
INPUT/OUTPUT SIGNAL CHART
*1: This signal is sent to the ECM through CAN communication line.
*2: ECM determines the start signal status by the signals of engine speed and battery voltage.
SYSTEM DESCRIPTION
The ignition timing is controlled by the ECM to maintain the best air-
fuel ratio for every running condition of the engine. The ignition tim-
ing data is stored in the ECM. This data forms the map shown.
The ECM receives information such as the injection pulse width and
camshaft position sensor signal. Computing this information, ignition
signals are transmitted to the power transistor.
e.g., N: 1,800 rpm, Tp: 1.50 msec
A °BTDC
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.
Air Conditioning Cut ControlEBS010WR
INPUT/OUTPUT SIGNAL CHART
*1: This signal is sent to the ECM through CAN communication line.
*2: ECM determines the start signal status by the signals of engine speed and battery voltage.Sensor Input Signal to ECM ECM function Actuator
Crankshaft position sensor (POS)
Engine speed*
2 and piston position
Ignition timing
controlPower 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
Park/neutral position (PNP) switch Gear position
Battery
Battery voltage*
2
Wheel sensor*1Vehicle speed
SEF742M
Sensor Input Signal to ECM ECM function Actuator
Air conditioner switch Air conditioner ON signal
Air conditioner
cut controlAir conditioner relay Throttle position sensor Throttle valve opening angle
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
Wheel sensor*
1Vehicle speed

TROUBLE DIAGNOSIS
EC-555
[QR (WITHOUT EURO-OBD)]
C
D
E
F
G
H
I
J
K
L
MA
EC

DATA MONITOR MODE
Monitored Item
×: Applicable
Monitored item
[Unit]ECM
INPUT
SIGNALSMAIN
SIG-
NALSDescription Remarks
ENG SPEED [rpm]××

Indicates the engine speed computed from the
signals of the crankshaft position sensor (POS)
and camshaft position sensor (PHASE).

Accuracy becomes poor if engine
speed drops below the idle rpm.

If the signal is interrupted while the
engine is running, an abnormal
value may be indicated.
MAS A/F SE-B1 [V]××

The signal voltage of the mass air flow sensor
is displayed.
When the engine is stopped, a
certain value is indicated.
B/FUEL SCHDL
[msec]×

“Base fuel schedule” indicates the fuel injection
pulse width programmed into ECM, prior to any
learned on board correction.
A/F ALPHA-B1 [%]×

The mean value of the air-fuel ratio feedback
correction factor per cycle is indicated.

When the engine is stopped, a
certain value is indicated.

This data also includes the data
for the air-fuel ratio learning con-
trol.
COOLAN TEMP/S
[°C] or [°F]××

The engine coolant temperature (determined by
the signal voltage of the engine coolant temper-
ature sensor) is displayed.

When the engine coolant tempera-
ture sensor is open or short-cir-
cuited, ECM enters fail-safe mode.
The engine coolant temperature
determined by the ECM is dis-
played.
HO2S1 (B1) [V]××

The signal voltage of the heated oxygen sensor
1 is displayed.
HO2S2 (B1) [V]×

The signal voltage of the heated oxygen sensor
2 is displayed.
HO2S1 MNTR (B1)
[RICH/LEAN]××

Display of heated oxygen sensor 1 signal dur-
ing air-fuel ratio feedback control:
RICH: means the mixture became “rich”, and
control is being affected toward a leaner mix-
ture.
LEAN: means the mixture became “lean”, and
control is being affected toward a rich mixture.
After turning ON the ignition
switch, “RICH” is displayed until
air-fuel mixture ratio feedback
control begins.

When the air-fuel ratio feedback is
clamped, the value just before the
clamping is displayed continu-
ously.
HO2S2 MNTR (B1)
[RICH/LEAN]×

Display of heated oxygen sensor 2 signal:
RICH: means the amount of oxygen after three
way catalyst is relatively small.
LEAN: means the amount of oxygen after three
way catalyst is relatively large.

When the engine is stopped, a
certain value is indicated.
VHCL SPEED SE
[km/h] or [mph]××

The vehicle speed computed from the vehicle
speed signal is displayed.
BATTERY VOLT
[V]××

The power supply voltage of ECM is displayed.
ACCEL SEN 1 [V]××

The accelerator pedal position sensor signal
voltage is displayed.
ACCEL SEN 2 signal is converted
by ECM internally. Thus, it differs
from ECM terminal voltage signal. ACCEL SEN 2 [V]×
THRTL SEN 1 [V]××

The throttle position sensor signal voltage is
displayed.
THRTL SEN 2 signal is converted
by ECM internally. Thus, it differs
from ECM terminal voltage signal. THRTL SEN 2 [V]×
INT/A TEMP SE
[°C] or [°F]××

The intake air temperature (determined by the
signal voltage of the intake air temperature sen-
sor) is indicated.

EC-556
[QR (WITHOUT EURO-OBD)]
TROUBLE DIAGNOSIS

START SIGNAL
[ON/OFF]××
Indicates start signal status [ON/OFF] com-
puted by the ECM according to the signals of
engine speed and battery voltage.
After starting the engine, [OFF] is
displayed regardless of the starter
signal.
CLSD THL POS
[ON/OFF]××

Indicates idle position [ON/OFF] computed by
ECM according to the accelerator pedal posi-
tion sensor signal.
AIR COND SIG
[ON/OFF]××

Indicates [ON/OFF] condition of the air condi-
tioner switch as determined by the air condi-
tioner signal.
P/N POSI SW
[ON/OFF]××

Indicates [ON/OFF] condition from the park/
neutral position (PNP) switch signal.
PW/ST SIGNAL
[ON/OFF]××

[ON/OFF] condition of the power steering pres-
sure sensor as determined by the power steer-
ing pressure sensor signal is indicated.
LOAD SIGNAL
[ON/OFF]××

Indicates [ON/OFF] condition from the electrical
load signal.
ON: Rear window defogger switch is ON and/or
lighting switch is in 2nd position.
OFF: Both rear window defogger switch and
lighting switch are OFF.
IGNITION SW
[ON/OFF]×

Indicates [ON/OFF] condition from ignition
switch.
HEATER FAN SW
[ON/OFF]×

Indicates [ON/OFF] condition from the heater
fan switch signal.
BRAKE SW
[ON/OFF]×

Indicates [ON/OFF] condition from the stop
lamp switch signal.
INJ PULSE-B1
[msec]×

Indicates the actual fuel injection pulse width
compensated by ECM according to the input
signals.
When the engine is stopped, a
certain computed value is indi-
cated.
IGN TIMING
[BTDC]×

Indicates the ignition timing computed by ECM
according to the input signals.
When the engine is stopped, a
certain value is indicated.
PURG VOL C/V
[%]

Indicates the EVAP canister purge volume con-
trol solenoid valve control value computed by
the ECM according to the input signals.

The opening becomes larger as the value
increases.
INT/V TIM (B1)
[°CA]

Indicates [°CA] of intake camshaft advanced
angle.
INT/V SOL (B1) [%]

The control value of the intake valve timing con-
trol solenoid valve (determined by ECM accord-
ing to the input signal) is indicated.

The advance angle becomes larger as the
value increases
VIAS S/V
[ON/OFF]

The control condition of the VIAS control sole-
noid 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 operat-
ing.
AIR COND RLY
[ON/OFF]×

The air conditioner relay control condition
(determined by ECM according to the input sig-
nals) is indicated. Monitored item
[Unit]ECM
INPUT
SIGNALSMAIN
SIG-
NALSDescription Remarks

TROUBLE DIAGNOSIS
EC-557
[QR (WITHOUT EURO-OBD)]
C
D
E
F
G
H
I
J
K
L
MA
EC

NOTE:
Any monitored item that does not match the vehicle being diagnosed is deleted from the display automatically.
DATA MONITOR (SPEC) MODE
Monitored Item
FUEL PUMP RLY
[ON/OFF]×
Indicates the fuel pump relay control condition
determined by ECM according to the input sig-
nals.
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]

Indicates the condition of the cooling fan (deter-
mined by ECM according to the input signals).
HI ... High speed operation
LOW: Low speed operation
OFF: Stop
HO2S1 HTR (B1)
[ON/OFF]

Indicates [ON/OFF] condition of heated oxygen
sensor 1 heater determined by ECM according
to the input signals.
HO2S2 HTR (B1)
[ON/OFF]

Indicates [ON/OFF] condition of heated oxygen
sensor 2 heater determined by ECM according
to the input signals.
IDL A/V LEARN
[YET/CMPLT]

Display 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.
AC PRESS SEN
[V]

The signal voltage from the refrigerant pressure
sensor is displayed.
Voltage [V]

Voltage, frequency, duty cycle or pulse width
measured by the probe.

Only “#” is displayed if item is
unable to be measured.

Figures with “#”s are temporary
ones. They are the same figures
as an actual piece of data which
was just previously measured. Frequency
[msec], [Hz] or [%]
DUTY-HI
DUTY-LOW
PLS WIDTH-HI
PLS WIDTH-LOWMonitored item
[Unit]ECM
INPUT
SIGNALSMAIN
SIG-
NALSDescription Remarks
Monitored item [Unit]ECM
input
signalsMain
signalsDescription Remarks
ENG SPEED [rpm]×

Indicates the engine speed computed
from the signals of the crankshaft posi-
tion sensor (POS) and camshaft position
sensor (PHASE).
MAS A/F SE-B1 [V]××

The signal voltage of the mass air flow
sensor specification is displayed.
When engine is running specification
range is indicated.
B/FUEL SCHDL
[msec]

“Base fuel schedule” indicates the fuel
injection pulse width programmed into
ECM, prior to any learned on board cor-
rection.

When engine is running specification
range is indicated.
A/F ALPHA-B1 [%]×

The mean value of the air-fuel ratio feed-
back correction factor per cycle is indi-
cated.
When engine is running specification
range is indicated.

This data also includes the data for the
air-fuel ratio learning control.

EC-566
[QR (WITHOUT EURO-OBD)]
TROUBLE DIAGNOSIS - SPECIFICATION VALUE

TROUBLE DIAGNOSIS - SPECIFICATION VALUEPFP:00031
DescriptionEBS010XG
The specification (SP) value indicates the tolerance of the value that is displayed in “DATA MONITOR (SPEC)”
mode of CONSULT-II during normal operation of the Engine Control System. When the value in “DATA MONI-
TOR (SPEC)” mode is within the SP value, the Engine Control System is confirmed OK. When the value in
“DATA MONITOR (SPEC)” 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 cor-
rection)

A/F ALPHA-B1 (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 ConditionEBS010XH

Vehicle driven distance: More than 5,000 km (3,017 miles)

Barometric pressure: 98.3 - 104.3 kPa (0.983 - 1.043 bar, 1.003 - 1.064 kg/cm2 , 14.25 - 15.12 psi)

Atmospheric temperature: 20 - 30°C (68 - 86°F)

Engine coolant temperature: 75 - 95°C (167 - 203°F)

Transmission: Warmed-up*1

Electrical load: Not applied*2

Engine speed: Idle
*1: For A/T models, 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).
For M/T models, after the engine is warmed up to normal operating temperature, drive vehicle for 5 minutes.
*2: Rear window defogger switch, air conditioner switch, lighting switch are OFF. Steering wheel is straight
ahead.
Inspection ProcedureEBS010XI
NOTE:
Perform “DATA MONITOR (SPEC)” mode in maximum scale display.
1. Perform EC-526, "
Basic Inspection" .
2. Confirm that the testing conditions indicated above are met.
3. Select “B/FUEL SCHDL”, “A/F ALPHA-B1” and “MAS A/F SE-
B1” in “DATA MONITOR (SPEC)” mode with CONSULT-II.
4. Make sure that monitor items are within the SP value.
5. If NG, go to EC-567, "
Diagnostic Procedure" .
SEF601Z

EC-582
[QR (WITHOUT EURO-OBD)]
DTC P0011 IVT CONTROL

DTC P0011 IVT CONTROLPFP:23796
DescriptionEBS010XU
SYSTEM DESCRIPTION
*: This signal is sent to the ECM through CAN communication line.
This mechanism hydraulically controls cam phases continuously with the fixed operating angle of the intake
valve.
The ECM receives signals such as crankshaft position, camshaft position, engine speed, and engine coolant
temperature. Then, the ECM sends ON/OFF pulse duty signals to the intake valve timing control solenoid
valve depending on driving status. This makes it possible to control the shut/open timing of the intake valve to
increase engine torque in low/mid speed range and output in high-speed range.
COMPONENT DISCRIPTION
Intake valve timing control solenoid valve is activated by ON/OFF
pulse duty (ratio) signals from the ECM.
The intake valve timing control solenoid valve changes the oil
amount and direction of flow through intake valve timing control unit
or stops oil flow.
The longer pulse width advances valve angle.
The shorter pulse width retards valve angle.
When ON and OFF pulse widths become equal, the solenoid valve
stops oil pressure flow to fix the intake valve angle at the control
position.
CONSULT-II Reference Value in Data Monitor ModeEBS010XV
Specification data are reference values.
Sensor Input signal to ECM ECM function Actuator
Crankshaft position sensor (POS)
Camshaft position sensor (PHASE)Engine speed
Intake valve
timing controlIntake valve timing control
solenoid valve Engine coolant temperature sensor Engine coolant temperature
Wheel sensor* Vehicle speed
PBIB0540E
PBIB1842E
MONITOR ITEM CONDITION SPECIFICATION
INT/V TIM (B1)

Engine: After warming up

Shift lever: N (A/T), Neutral (M/T)

Air conditioner switch: OFF

No loadIdle−5° - 5°CA
2,000 rpm Approx. 0° - 20°CA

EC-928
[YD (WITH EURO-OBD)]
TROUBLE DIAGNOSIS

DATA MONITOR MODE
COOLANT TEMP [°C] or
[°F]
The engine coolant temperature at the moment a malfunction is detected is displayed.
ENGINE SPEED [rpm]

The engine speed at the moment a malfunction is detected is displayed.
VEHICL SPEED [km/h] or
[mph]

The vehicle speed at the moment a malfunction is detected is displayed.
INT MANI PRES [kPa]

The intake manifold pressure at the moment a malfunction is detected is displayed. Freeze frame data item Description
MONITOR ITEMECM
INPUT
SIGNALMAIN
SIG-
NALSCONDITION SPECIFICATION
CKPS·RPM (TDC) [rpm]××

The engine speed computed from the
crankshaft position sensor signal is dis-
played.
COOLAN TEMP/S
[°C] or [°F]××

The engine coolant temperature (deter-
mined by the signal voltage of the engine
coolant temperature sensor) is dis-
played.When the engine coolant temper-
ature circuit is open or short, ECM
enters fail-safe mode. The engine
coolant temperature determined
by the ECM is displayed.
VHCL SPEED SE
[km/h] or [mph]××

The vehicle speed computed form the
vehicle speed sensor signal is displayed.
FUEL TEMP SEN
[°C] or [°F]××

The fuel temperature (determined by the
signal voltage of the fuel pump tempera-
ture sensor) is displayed.
ACCEL POS SEN [V]××

The accelerator pedal position sensor 1
signal voltage is displayed.
ACCEL SEN 2 [V]××

The accelerator pedal position sensor 2
signal voltage is displayed.
ACT CR PRESS [MPa]××

The Fuel rail pressure (determined by
the signal voltage of the fuel rail pressure
sensor) is displayed.
BATTERY VOLT [V]××

The power supply voltage of ECM is dis-
played.
P/N POSI SW [ON/OFF]××

Indicates [ON/OFF] condition from the
park/neutral position switch signal.
START SIGNAL [ON/OFF]××

indicates [ON/OFF] condition from the
starter signal.
PW/ST SIGNAL [ON/OFF]×

indicates [ON/OFF] condition from the
power steering pressure switch signal.
BRAKE SW [ON/OFF]××

indicates [ON/OFF] condition from the
stop lamp switch signal.
IGN SW [ON/OFF]××

Indicates [ON/OFF] condition from igni-
tion switch signal.
MAS AIR/FL SE [V]××

The signal voltage of the mass air flow
sensor is displayed.
MAIN INJ WID [msec]×

Indicates the actual fuel injection pulse
width compensated by ECM according to
the input signals.
PUMP CURRENT [mA]×

Indicates the fuel pump power supply
current from the ECM.
GLOW RLY [ON/OFF]×

The glow relay control condition (deter-
mined by ECM according to the input sig-
nal) is displayed.