2001 NISSAN X-TRAIL sensor

ENGINE CONTROL SYSTEM
EC-1399
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EC
System ChartEBS0037B
*: The input signals are sent to the ECM through CAN communication line.
Fuel Injection Control SystemEBS0036G
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 exchanged between ECM and Electronic Drive Unit (EDU). EDU controls fuel injectors
according to the input signals to adjust the amount of fuel injected to the 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 common rail fuel 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
●Accelerator pedal released position switch
●Common rail fuel pressure sensor
●Fuel temperature sensor
●Engine coolant temperature sensor
●Crankshaft position sensor (TDC)
●Camshaft position sensor
●Vehicle speed sensor
●ESP/TCS/ABS control unit*
●Ignition switch
●Stop L amp s witch
●Air conditioner switch
●Mass air flow sensor
●Park/neutral position switch
●Battery voltage
●Power steering oil pressure switch Fuel injection controlEDU, Fuel injectors and Suction control
valve
Fuel injection timing controlEDU, Fuel injectors and Suction control
valve
Fuel cut controlEDU, Fuel injectors and Suction control
valve
Glow control system Glow relay & glow indictor lamp
On board diagnostic system Malfunction indicator (MI)
EGR volume control EGR volume control valve
Cooling fan control Cooling fan 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)EDU
Fuel injectors
Suction control valve Crankshaft position sensor (TDC) Engine speed
Camshaft position sensor Piston position
Ignition switch Start signal
Common rail fuel pressure sensor Common rail fuel pressure
SEF648S

EC-1400
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ENGINE CONTROL SYSTEM
IDLE CONTROL
Input/Output Signal Chart
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
(TDC) detects engine speed, the accelerator pedal position sensor
detects accelerator pedal position and common rail fuel pressure
sensor detects common rail fuel pressure. These sensors send sig-
nals to the ECM.
The fuel injection data, predetermined by correlation between vari-
ous engine speeds, accelerator pedal positions and common rail fuel
pressure 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)EDU
Fuel injectors
Suction control valve Crankshaft position sensor (TDC) Engine speed
Battery Battery voltage
Accelerator pedal position sensor Accelerator pedal position
Accelerator pedal released position switch Accelerator pedal released position
Vehicle speed sensor Vehicle speed
Air conditioner switch Air conditioner signal
Common rail fuel pressure sensor Common rail fuel pressure
Sensor Input Signal to ECM ECM Function Actuator
Crankshaft position sensor (TDC) Engine speed
Fuel injection
control (Nor-
mal control)EDU
Fuel injectors
Suction control valve Accelerator pedal position sensor Accelerator position
Common rail fuel pressure sensor Common rail fuel pressure
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Sensor Input Signal to ECM ECM Function Actuator
Mass air flow sensor Amount of intake air
Fuel injection
control (Maxi-
mum amount
control)EDU
Fuel Injectors Engine coolant temperature sensor Engine coolant temperature
Crankshaft position sensor (TDC) Engine speed
Accelerator pedal position sensor Accelerator position

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

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.
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PBIB0411E

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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TROUBLE DIAGNOSIS
EC-1411
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Description for Work Flow
DIAGNOSTIC WORK SHEET
There are many operating conditions that lead to the malfunction of
engine components. A good grasp of such conditions can make trou-
bleshooting faster and more accurate.
In general, each customer feels differently about an incident. It is
important to fully understand the symptoms or conditions for a cus-
tomer complaint.
Utilize a diagnostic worksheet like the one shown below in order to
organize all the information for troubleshooting.
STEP DESCRIPTION
STEP IGet detailed information about the conditions and the environment when the incident/symptom occurred using the
EC-1411, "
DIAGNOSTIC WORK SHEET" .
STEP IIBefore confirming the concern, check and write down (print out using CONSULT-II) the DTC, then erase the DTC.
Refer to EC-1406
.
If the incident cannot be verified, perform EC-1441, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
Study the relationship between the cause, specified by DTC, and the symptom described by the customer. (The
“Symptom Matrix Chart” will be useful. Refer to EC-1416
.) Also check related service bulletins for information.
STEP IIITry to confirm the symptom and under what conditions the incident occurs.
The “DIAGNOSTIC WORK SHEET” is useful to verify the incident. Connect CONSULT-II to the vehicle in DATA
MONITOR (AUTO TRIG) mode and check real time diagnosis results.
If the incident cannot be verified, perform EC-1441, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
If the malfunction code is detected, skip STEP IV and perform STEP V.
STEP IVTry to detect the DTC by driving in (or performing) the “DTC Confirmation Procedure”. Check and read the DTC by
using CONSULT-II.
During the DTC verification, be sure to connect CONSULT-II to the vehicle in DATA MONITOR (AUTO TRIG) mode
and check real time diagnosis results.
If the incident cannot be verified, perform EC-1441, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
In case the “DTC Confirmation Procedure” is not available, perform the “Overall Function Check” instead. The DTC
cannot be displayed by this check, however, this simplified “check” is an effective alternative.
The “NG” result of the “Overall Function Check” is the same as the DTC detection.
STEP VTake the appropriate action based on the results of STEP I through IV.
If the malfunction code is indicated, proceed to Trouble Diagnosis for DTC PXXXX.
If the normal code is indicated, proceed to the Basic Inspection, EC-1412
. Then perform inspections according to the
Symptom Matrix Chart. Refer to EC-1416
.
STEP VIIdentify where to begin diagnosis based on the relationship study between symptom and possible causes. Inspect the
system for mechanical binding, loose connectors or wiring damage using (tracing) “Harness Layouts”.
Gently shake the related connectors, components or wiring harness with CONSULT-II set in “DATA MONITOR (AUTO
TRIG)” mode.
Check the voltage of the related ECM terminals or monitor the output data from the related sensors with CONSULT-II.
Refer to EC-1425
or EC-1437 .
The “Diagnostic Procedure” in EC section contains a description based on open circuit inspection. A short circuit
inspection is also required for the circuit check in the Diagnostic Procedure. For details, refer to GI-23, "
How to Per-
form Efficient Diagnosis for an Electrical Incident" , “Circuit Inspection”.
Repair or replace the malfunction parts.
If the malfunctioning part cannot be detected, perform EC-1441, "
TROUBLE DIAGNOSIS FOR INTERMITTENT
INCIDENT" .
STEP VIIOnce you have repaired the circuit or replaced a component, you need to run the engine in the same conditions and
circumstances which resulted in the customer's initial complaint.
Perform the “DTC Confirmation Procedure” and confirm the normal code (DTC P0000) is detected. If the incident is
still detected in the final check, perform STEP VI by using a different method from the previous one.
Before returning the vehicle to the customer, be sure to erase the unnecessary (already fixed) DTC in ECM. (Refer to
EC-1406
.)
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TROUBLE DIAGNOSIS
EC-1413
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1.INSPECTION START
1. Check service records for any recent repairs that may indicate a related incident.
2. Check the current need for scheduled maintenance, especially for fuel filter and air cleaner filter. Refer to
MA-7, "
PERIODIC MAINTENANCE" .
3. Open engine hood and check the following:
–Harness connectors for improper connections
–Vacuum hoses for splits, kinks, or improper connections
–Wiring for improper connections, pinches, or cuts
4. Start engine and warm it up to the normal operating tempera-
ture.
>> GO TO 2.
2.PREPARATION FOR CHECKING IDLE SPEED
With CONSULT-II
Connect CONSULT-II to the data link connector.
>> GO TO 3.
3.CHECK IDLE SPEED
With CONSULT-II
1. Select “CKPS·RPM (TDC)” in “DATA MONITOR” mode with CONSULT-II.
2. Read idle speed.
OK or NG
OK >>INSPECTION END
NG >> GO TO 4.
4.CHECK FOR INTAKE AIR LEAK
Listen for an intake air leak after the mass air flow sensor.
OK or NG
OK >> GO TO 5.
NG >> Repair or replace.
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725±25 rpm
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