NISSAN X-TRAIL 2001 Service Repair Manual

ENGINE CONTROL SYSTEM
EC-1401
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EC
DECELERATION CONTROL
Input/Output Signal Chart
The ECM sends a fuel cut signal to the fuel injector and suction control valve during deceleration for better fuel
efficiency. The ECM determines the time of deceleration according to signals from the accelerator pedal
released position switch and crankshaft position sensor (TDC).
Fuel Injection Timing Control SystemEBS0036H
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 ControlEBS0036I
INPUT / OUTPUT SIGNAL CHART
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)EBS0036J
INPUT/OUTPUT SIGNAL CHART
If the engine speed is above 2,800 rpm with no load (for example, in neutral and engine speed 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 operate until the engine speed reaches 1,500 rpm, then fuel cut is cancelled.
NOTE:
This function is different from deceleration control listed under EC-1399, "
Fuel Injection Control Sys-
tem" .
Sensor Input Signal to ECM ECM Function Actuator
Accelerator pedal released position switch Accelerator pedal position Fuel injection
control (Decel-
eration control)EDU
Fuel injectors
Crankshaft position sensor (TDC) 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 controlEDU
Fuel injectors Accelerator pedal released position switch Accelerator position
Crankshaft position sensor (TDC) Engine speed

EC-1402
[YD]
ENGINE CONTROL SYSTEM
Crankcase Ventilation System
EBS0036K
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 CommunicationEBS00NBH
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

ENGINE CONTROL SYSTEM
EC-1403
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EC
FOR M/T MODELS WITH ESP
System diagram
Input/output signal chart
T: Transmit R: Receive
SKIA0885E
Signals ECMSteering wheel
angle sensor4WD control unitESP/ TCS / ABS
control unit
Engine speed signal T R R
Accelerator pedal position signal T R
ESP operation signal R R T
TCS operation signal R R T
ABS operation signal R R T
Stop lamp switch signalRT
Steering wheel angle sensor signal T R
ESP-OFF switch signalRT
Wheel speed sensor signalRT
4WD mode signalTR

EC-1404
[YD]
BASIC SERVICE PROCEDURE
BASIC SERVICE PROCEDURE
PFP:00018
Fuel FilterEBS0036N
DESCRIPTION
A water draining cock is on the lower side and a priming pump for bleeding air is on the upper side.
AIR BLEEDING
Pump the priming pump to bleed air.
●When air is bled completely, the pumping of the priming pump
suddenly becomes heavy. Stop the operation at that time.
●If it is difficult to bleed air by the pumping of the priming pump
(the pumping of the priming pump does not become heavy), dis-
connect the fuel supply hose between the fuel filter and the fuel
gallery. Then, perform the operation described above, and make
sure that fuel comes out. (Use a pan, etc. so as not to spill fuel.
Do not let fuel get on engine and other parts.) After that, connect
the hose, then bleed air again.
●Start engine and let it idle for at least one minute after perform-
ing air bleeding.
WATER DRAINING
1. Remove the fuel filter, filter bracket, protector assembly from the dash panel as follows.
a. Remove the air cleaner case (upper), air duct assembly, and vacuum hose for brake booster (between the
vacuum pump and vacuum pipe).
CAUTION:
After the duct is removed, cover the opening with gum tape, etc. to prevent foreign object from
getting into the engine during the operation.
b. Remove the mounting nuts on the dash panel, then remove the fuel filter, filter bracket, and protector
assembly from the dash panel.
●It is not necessary to disconnect the fuel hose.
2. Using a tool such as a pliers, loosen the water draining cock at the bottom of the fuel filter.
Accelerator Pedal Released Position LearningEBS009NW
DESCRIPTION
"Accelerator Pedal Released Position Learning" is an operating to learn the fully released position of the
accelerator pedal by monitoring the accelerator pedal position sensor output signal. It must be performed
when accelerator work unit or ECM is replaced.
OPERATION PROCEDURE
1. Turn ignition switch "ON".
2. Select "OFF ACCEL PO SIG" in "ACTIVE TEST" mode with
CONSULT-II
3. Make sure that accelerator pedal is released.
SEF375Y
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BASIC SERVICE PROCEDURE
EC-1405
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4. Touch "CLEAR" and wait a few seconds.
5. Make sure that "CMPLT" is displayed on CONSULT-II screen.
Fuel Pressure Relief ValveEBS009PB
DESCRIPTION
When the fuel pressure in common rail increases to excessively high, fuel pressure relief valve opens to carry
excess fuel to the return hose.
FUEL PRESSURE RELIEF VALVE CHECK
WARNING:
Confirm that the engine is cooled down and there are no fire hazards near the vehicle.
1. Turn ignition switch "OFF".
2. Remove fuel hose from fuel pressure relief valve.
3. Attach a blind cap or plug to removed hose.
4. Turn ignition switch "ON".
5. Select "PRES REGULATOR" in "ACTIVE TEST MODE" with
CONSULT-II.
6. Start engine and keep engine speed 2,000 rpm.
7. Raise fuel pressure to 135 MPa with touching "UP" or "Qu" on
the CONSULT-II screen.
8. Confirm that the fuel does not come out from the fuel pressure
relief valve.
WARNING:
If the fuel comes out, stop the engine immediately.
9. If NG, replace common rail.
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EC-1406
[YD]
ON BOARD DIAGNOSTIC (OBD) SYSTEM
ON BOARD DIAGNOSTIC (OBD) SYSTEM
PFP:00028
DTC and MI Detection LogicEBS0037C
When a malfunction is detected, the malfunction (DTC) is stored in the ECM memory.
The MI will light up each time the ECM detects malfunction. For diagnostic items causing the MI to light up,
refer to EC-1393, "
INDEX FOR DTC" .
Diagnostic Trouble Code (DTC)EBS0037D
HOW TO READ DTC
The DTC can be read by CONSULT-II only.
With CONSULT-II
CONSULT-II displays the DTC in "SELF-DIAG RESULTS" mode. Example: P0115, P0335, P1233, etc. These
DTCs are prescribed by ISO15031-6.
(CONSULT-II also displays the malfunctioning component or system.)
HOW TO ERASE DTC
How to Erase DTC ( With CONSULT-II)
1. If the ignition switch stays “ON” after repair work, be sure to turn ignition switch “OFF” once. Wait at least
5 seconds and then turn it “ON” (engine stopped) again.
2. Touch “ENGINE”.
3. Touch “SELF-DIAG RESULTS”.
4. Touch “ERASE”. (The DTC in the ECM will be erased.)
The emission related diagnostic information in the ECM can be erased by selecting “ERASE” in the “SELF-
DIAG RESULTS” mode with CONSULT-II.
NATS (Nissan Anti-theft System)EBS008YE
●If the security indicator lights up with the ignition switch in
the "ON" position or "NATS MALFUNCTION" is displayed
on "SELF-DIAG RESULTS" screen, perform self-diagnostic
results mode with CONSULT-II using NATS program card.
Refer to NATS (Nissan Anti-Theft System) in BL section.
●Confirm no self-diagnostic results of NATS is displayed
before touching "ERASE" in "SELF-DAIG RESULTS" mode
with CONSULT-II.
●When replacing ECM, initialization of NATS system and reg-
istration of all NATS ignition key IDs must be carried out
with CONSULT-II using NATS program card.
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SEF543X

ON BOARD DIAGNOSTIC (OBD) SYSTEM
EC-1407
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Therefore, be sure to receive all keys from vehicle owner. Regarding the procedure of NATS initial-
ization and NATS ignition key ID registration, refer to CONSULT-II operation manual, NATS.
Malfunction Indicator (MI)EBS0036Q
DESCRIPTION
The MI is located on the instrument panel.
1. The MI will light up when the ignition switch is turned ON without
the engine running. This is a bulb check.
●If the MI does not light up, refer to DI-43, "WARNING LAMPS"
or see EC-1573 .
2. When the engine is started, the MI should go off.
If the MI remains on, the on board diagnostic system has
detected an engine system malfunction.
On Board Diagnostic System Function
The on board diagnostic system has the following two functions.
Diagnostic Test Mode I - Bulb Check
In this mode, the MI on the instrument panel should stay ON. If it remains OFF, check the bulb. Refer to DI-43,
"WARNING LAMPS" or see EC-1573 .
Diagnostic Test Mode I - Malfunction Warning
SAT652J
Diagnostic Test
ModeKEY and ENG.
Statu sFunction Explanation of Function
Mode I Ignition switch in
ON position
Engine stoppedBULB CHECK This function checks the MI bulb for damage (blown, open
circuit, etc.).
If the MI does not come on, check MI circuit. (See EC-
1573, "MI& DATA LINK CONNECTORS" .)
Engine running MALFUNCTION
WARNINGThis is a usual driving condition. When ECM detects a mal-
function, the MI will light up to inform the driver that a mal-
function has been detected.
MI Condition
ON When the malfunction is detected or the ECM's CPU is malfunctioning.
OFF No malfunction.

EC-1408
[YD]
ON BOARD DIAGNOSTIC (OBD) SYSTEM
Relationship Between MI, DTC, CONSULT-II and Driving Patterns
*1: When a malfunction is detected, MI
will light up.*2: MI will not light up after ignition
switch is turned OFF.*3: When a malfunction is detected for
the first time, the DTC will be stored
in ECM.
*4: The DTC will not be displayed any
longer after vehicle is driven 40 times
without the same malfunction. (The
DTC still remain in ECM.)*5: Other screens except SELF-DIAG-
NOSTIC RESULTS & DATA MONI-
TOR (AUTO TRIG) cannot display
the malfunction. DATA MONITOR
(AUTO TRIG) can display the mal-
function at the moment it is detected.
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TROUBLE DIAGNOSIS
EC-1409
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TROUBLE DIAGNOSISPFP:00004
Trouble Diagnosis IntroductionEBS0036Z
INTRODUCTION
The engine has an ECM to control major systems such as fuel injec-
tion control, fuel injection timing control, glow control system, etc.
The ECM accepts input signals from sensors and instantly actuators.
It is essential that both input and output signals are proper and sta-
ble. At the same time, it is important that there are no malfunctions
such as vacuum leaks, or other malfunctions with the engine.
It is much more difficult to diagnose a malfunction that occurs inter-
mittently rather than continuously. Most intermittent malfunctions are
caused by poor electric connections or improper wiring. In this case,
careful checking of suspected circuits may help prevent the replace-
ment of good parts.
A visual check only may not find the cause of the incidents. A road
test with CONSULT-II or a circuit tester connected should be per-
formed. Follow the EC-1410, "
WORK FLOW" .
Before undertaking actual checks, take a few minutes to talk with a
customer who approaches with a driveability complaint. The cus-
tomer can supply good information about such incidents, especially
intermittent ones. Find out what symptoms are present and under
what conditions they occur. A “Diagnostic Worksheet” like the exam-
ple on next page should be used.
Start your diagnosis by looking for “conventional” incidents first. This
will help troubleshoot driveability incidents on an electronically con-
trolled engine vehicle.
MEF036D
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EC-1410
[YD]
TROUBLE DIAGNOSIS
WORK FLOW
*1 If time data of “SELF-DIAG
RESULTS” is other than “0”, per-
form EC-1441, "
TROUBLE DIAG-
NOSIS FOR INTERMITTENT
INCIDENT" .*2 If the incident cannot be verified, per-
form EC-1441, "
TROUBLE DIAG-
NOSIS FOR INTERMITTENT
INCIDENT" .*3 If the on board diagnostic system
cannot be performed, check main
power supply and ground circuit.
Refer to EC-1442, "POWER SUP-
PLY CIRCUIT FOR ECM" .
*4 If malfunctioning part cannot be
detected, perform EC-1441, "
TROU-
BLE DIAGNOSIS FOR INTERMIT-
TENT INCIDENT" .
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