2001 NISSAN X-TRAIL Line pressure

EC-736
[QR25(WITHOUT EURO-OBD)]
REFRIGERANT PRESSURE SENSOR
4. CHECK REFRIGERANT PRESSURE SENSOR GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch “OFF”.
2. Check harness continuity between refrigerant pressure sensor terminal 1 and engine ground.
Refer to Wiring Diagram.
3. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 6.
NG >> GO TO 5.
5. DETECT MALFUNCTIONING PART
Check the following.
●Harness connectors E61, F38
●Harness for open or short between ECM and refrigerant pressure sensor
>> Repair open circuit or short to ground or short to power in harness or connectors.
6. CHECK REFRIGERANT PRESSURE SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Disconnect ECM harness connector.
2. Check harness continuity between ECM terminal 83 and refrigerant pressure sensor terminal 2.
Refer to Wiring Diagram.
3. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 8.
NG >> GO TO 7.
7. DETECT MALFUNCTIONING PART
Check the following.
●Harness connectors E61, F38
●Harness for open or short between ECM and refrigerant pressure sensor
>> Repair open circuit or short to ground or short to power in harness or connectors.
8. CHECK INTERMITTENT INCIDENT
Refer to EC-115, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
OK or NG
OK >> Replace refrigerant pressure sensor.
NG >> Repair or replace.
Removal and InstallationEBS00NL6
REFRIGERANT PRESSURE SENSOR
Refer to ATC-129, "REFRIGERANT LINES" . Continuity should exist.
Continuity should exist.

ENGINE CONTROL SYSTEM
EC-765
[QR20(WITH EURO-OBD)]
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EC
System ChartEBS00MSA
*1: This sensor is not used to control the engine system under normal conditions.
*2: These signals are sent to the ECM through CAN communication line.
Multiport Fuel Injection (MFI) SystemEBS00MSB
INPUT/OUTPUT SIGNAL CHART
*1: Under normal conditions, this sensor is not for engine control operation.
*2: This signal is sent to the ECM through CAN communication line. Input (Sensor) ECM Function Output (Actuator)
●Camshaft position sensor (PHASE)
●Crankshaft position sensor (POS)
●Mass air flow sensor
●Engine coolant temperature sensor
●Heated oxygen sensor 1
●Throttle position sensor
●Accelerator pedal position sensor
●Park/neutral position (PNP) switch
●Intake air temperature sensor
●Power steering pressure sensor
●Ignition switch
●Battery voltage
●Knock sensor
●Refrigerant pressure sensor
●Heated oxygen sensor 2 *1
●TCM (Transmission control module) *2
●ESP/TCS/ABS control unit *2
●Wheel sensor
●Air conditioner switch
●Electrical loadFuel injection & mixture ratio control Fuel injectors
Electronic ignition system Power transistors
Fuel pump control Fuel pump relay
On board diagnostic system MI (On the instrument panel)
Heated oxygen sensor 1 heater control Heated oxygen sensor 1 heater
Heated oxygen sensor 2 heater control Heated oxygen sensor 2 heater
EVAP canister purge flow controlEVAP canister purge volume control
solenoid valve
Air conditioning cut control Air conditioner relay
Cooling fan control Cooling fan relays
Sensor Input Signal to ECMECM func-
tionActuator
Crankshaft position sensor (POS)
Engine speed
Piston position
Fuel injec-
tion & mix-
ture ratio
controlFuel injectors Camshaft position sensor (PHASE)
Mass air flow sensor Amount of intake air
Engine coolant temperature sensor Engine coolant temperature
Heated oxygen sensor 1 Density of oxygen in exhaust gas
Throttle position sensor Throttle position
Accelerator pedal position sensor Accelerator pedal position
Park/neutral position (PNP) switch Gear position
Ignition switch Start signal
Knock sensor Engine knocking condition
Battery Battery voltage
Power steering pressure sensor Power steering operation
Heated oxygen sensor 2 *1 Density of oxygen in exhaust gas
ESP/TCS/ABS control unit *2 ESP/TCS operation command
Wheel sensor Vehicle speed
Air conditioner switch Air conditioner operation

ENGINE CONTROL SYSTEM
EC-769
[QR20(WITH EURO-OBD)]
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EC
●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.
Fuel Cut Control (at No Load and High Engine Speed)EBS00MSE
INPUT/OUTPUT SIGNAL CHART
SYSTEM DESCRIPTION
If the engine speed is above 1,800 rpm with no load (for example, in neutral and engine speed over 1,800
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 “Multiport Fuel Injection (MFI) System”, EC-765
.
CAN CommunicationEBS00NBG
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.
FOR A/T MODELS
System diagram
Input/output signal chart
T: Transmit R: Receive Sensor Input Signal to ECMECM func-
tionActuator
Park/neutral position (PNP) switch Neutral position
Fuel cut
controlFuel injectors Throttle position sensor Throttle position
Accelerator pedal position sensor Accelerator pedal position
Engine coolant temperature sensor Engine coolant temperature
Crankshaft position sensor (POS) Engine speed
Wheel sensor Vehicle speed
SKIA0884E
Signals ECM TCM
Engine coolant temperature signal T R
Accelerator pedal position signal T R
A/T self-diagnosis signal R T

BASIC SERVICE PROCEDURE
EC-775
[QR20(WITH EURO-OBD)]
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It is useful to perform EC-843, "TROUBLE DIAGNOSIS - SPECIFICATION VALUE" .
5.If any of the following conditions occur after the engine has started, eliminate the cause of the
incident and perform “Idle air volume learning” all over again:
–Engine stalls.
–Erroneous idle.
Fuel Pressure CheckEBS00MSK
FUEL PRESSURE RELEASE
Before disconnecting fuel line, release fuel pressure from fuel line to eliminate danger.
NOTE:
Prepare pans or saucers under the disconnected fuel line because the fuel may spill out. The fuel pres-
sure cannot be completely released because QR engine models do not have fuel return system.
With CONSULT-II
1. Turn ignition switch “ON”.
2. Perform “FUEL PRESSURE RELEASE” in “WORK SUPPORT”
mode with CONSULT-II.
3. Start engine.
4. After engine stalls, crank it two or three times to release all fuel
pressure.
5. Turn ignition switch “OFF”.
Without CONSULT-II
1. Remove fuel pump fuse located in fuse box.
2. Start engine.
3. After engine stalls, crank it two or three times to release all fuel
pressure.
4. Turn ignition switch “OFF”.
5. Reinstall fuel pump fuse after servicing fuel system.
FUEL PRESSURE CHECK
CAUTION:
●The fuel hose connection method used when taking fuel pressure check must not be used for
other purposes.
●Take care for not to scratch and not to put debris around connection area when servicing, so that
the quick connector keeps sealability with O-rings inside.
1. Release fuel pressure to zero. Refer to EC-775, "
FUEL PRESSURE RELEASE" .
2. Prepare fuel hose for fuel pressure check, and connect fuel pressure gauge.
●Use suitable fuel hose for fuel pressure check (genuine NISSAN fuel hose without quick connector).
●To avoid unnecessary force or tension to hose, use moderately long fuel hose for fuel pressure check.
●Do not use the fuel hose for checking fuel pressure with damage or cracks on it.
●Use Pressure Gauge to check fuel pressure.
3. Remove fuel hose. Refer to EM-16, "
INTAKE MANIFOLD" .
●Do not twist or kink fuel hose because it is plastic hose.
●Do not remove fuel hose from quick connector.
●Keep the original fuel hose to be free from intrusion of dust or foreign substances with a suitable cover.
SEF214Y
PBIB0508E

EC-776
[QR20(WITH EURO-OBD)]
BASIC SERVICE PROCEDURE
4. Install the fuel pressure gauge as shown in the figure.
●Wipe off oil or dirt from hose insertion part using cloth moist-
ened with gasoline.
●Apply proper amount of gasoline between top of the fuel tube
and No.1 spool.
●Insert fuel hose for fuel pressure check until it touches the
No.1 spool on fuel tube.
●Use NISSAN genuine hose clamp (part number: 16439
N4710 or 16439 40U00).
●When reconnecting fuel line, always use new clamps.
●When reconnecting fuel hose, check the original fuel hose for
damage and abnormality.
●Use a torque driver to tighten clamps.
●Install hose clamp to the position within 1 - 2 mm (0.04 - 0.08
in).
●Make sure that clamp screw does not contact adjacent parts.
5. After connecting fuel hose for fuel pressure check, pull the hose
with a force of approximately 98 N (10 kg, 22 lb) to confirm fuel
tube does not come off.
6. Turn ignition switch “ON”, and check for fuel leakage.
7. Start engine and check for fuel leakage.
8. Read the indication of fuel pressure gauge.
●Do not perform fuel pressure check with system operating. Fuel pressure gauge may indicate false
readings.
●During fuel pressure check, confirm for fuel leakage from fuel connection every 3 minutes.
9. If result is unsatisfactory, go to next step.
10. Check the following.
●Fuel hoses and fuel tubes for clogging
●Fuel filter for clogging
●Fuel pump
●Fuel pressure regulator for clogging
If OK, replace fuel pressure regulator.
If NG, repair or replace.Tightening torque: 1 - 1.5 N·m (0.1 - 0.15 kg-m,
9 - 13 in-lb)
At idling:
Approximately 350 kPa (3.5 bar, 3.57 kg/cm
2 , 51 psi)
PBIB0669E
PBIB0670E

TROUBLE DIAGNOSIS
EC-803
[QR20(WITH EURO-OBD)]
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Fail-safe ChartEBS00MST
The ECM enters fail-safe mode, if any of the following malfunctions is detected due to the open or short circuit.
When the ECM enters the fail-safe mode, the MI illuminates.
Priority Detected items (DTC)
1
●U1000 CAN communication line
●P0102 P0103 P1102 Mass air flow sensor
●P0112 P0113 Intake air temperature sensor
●P0117 P0118 Engine coolant temperature sensor
●P0120 Throttle position sensor
●P0121 Accelerator pedal position sensor
●P0327 P0328 Knock sensor
●P0335 Crankshaft position sensor (POS)
●P0340 Camshaft position sensor (PHASE)
●P0500 Vehicle speed sensor
●P0605 ECM
●P0705 Park/Neutral position (PNP) sensor
●P1706 Park/Neutral position (PNP) switch
2
●P0031 P0032 Heated oxygen sensor 1 heater
●P0037 P0038 Heated oxygen sensor 2 heater
●P0132 P0133 P0134 P1143 P1144 Heated oxygen sensor 1
●P0138 P0139 P1146 P1147 Heated oxygen sensor 2
●P0444 P0445 EVAP canister purge volume control solenoid valve
●P0550 Power steering pressure sensor
●P0650 MI
●P0710-P0725, P0740-P0755, P1705 P1760 A/T related sensors and solenoid valves
●P1065 ECM power supply
●P 1111 I n ta k e v a l v e t i m i n g c o n t r o l s o l e n o i d v a l v e
●P1122 Electric throttle control function
●P1123 Throttle control motor relay
●P1212 ESP/TCS/ABS communication line
●P1805 Brake switch
3
●P0011 Intake valve timing control
●P0171 P0172 Fuel injection system function
●P0300 - P0304 Misfire
●P0420 Three way catalyst function
●P0731-P0734 A/T function
●P1121 Electric throttle control actuator
●P1217 Engine over temperature (OVERHEAT)
DTC No. Detected items Engine operating condition in fail-safe mode
P0102
P0103
P1102Mass air flow sensor circuit Engine speed will not rise more than 2,400 rpm due to the fuel cut.

EC-828
[QR20(WITH EURO-OBD)]
TROUBLE DIAGNOSIS
2. Connect “CONSULT-II” to data link connector, which is located
under LH dash panel near the fuse box cover.
3. Turn ignition switch ON.
4. Touch “START (NISSAN BASED VHCL)”.
5. Touch “ENGINE”.
If “ENGINE” is not indicated, go to GI-34, "
CONSULT-II Data
Link Connector (DLC) Circuit" .
6. Perform each diagnostic test mode according to each service
procedure.
For further information, see the CONSULT-II Operation Manual.
WORK SUPPORT MODE
Work Item
PBIB0376E
MBIB0233E
SEF995X
SEF824Y
WORK ITEM CONDITION USAGE
FUEL PRESSURE RELEASE
●FUEL PUMP WILL STOP BY TOUCHING “START” DUR-
ING IDLING.
CRANK A FEW TIMES AFTER ENGINE STALLS.When releasing fuel pressure
from fuel line
IDLE AIR VOL LEARN
●THE IDLE AIR VOLUME THAT KEEPS THE ENGINE
WITHIN THE SPECIFIED RANGE IS MEMORIZED IN
ECM.When learning the idle air volume

TROUBLE DIAGNOSIS
EC-829
[QR20(WITH EURO-OBD)]
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*: This function is not necessary in the usual service procedure.
SELF-DIAG RESULTS MODE
Self Diagnostic Item
Regarding items of “DTC and 1st trip DTC”, refer to EC-753, "INDEX FOR DTC" .)
Freeze Frame Data and 1st Trip Freeze Frame Data
*1: The items are the same as those of 1st trip freeze frame data. SELF-LEARNING CONT
●THE COEFFICIENT OF SELF-LEARNING CONTROL
MIXTURE RATIO RETURNS TO THE ORIGINAL COEF-
FICIENT.When releasing fuel pressure
from fuel line
TARGET IDLE RPM ADJ*
●IDLE CONDITION When setting target idle speed
TARGET IGNITION TIMING ADJ*
●IDLE CONDITION When adjusting target ignition tim-
ing WORK ITEM CONDITION USAGE
Freeze frame data
item*1Description
DIAG TROUBLE
CODE
[PXXXX]
●The engine control component part/control system has a trouble code, it is displayed as “PXXXX”. (Refer
to EC-753, "
INDEX FOR DTC" .)
FUEL SYS-B1
●“Fuel injection system status” at the moment a malfunction is detected is displayed.
●One mode in the following is displayed.
“MODE 2”: Open loop due to detected system malfunction
“MODE 3”: Open loop due to driving conditions (power enrichment, deceleration enrichment)
“MODE 4”: Closed loop - using oxygen sensor(s) as feedback for fuel control
“MODE 5”: Open loop - has not yet satisfied condition to go to closed loop
CAL/LD VALUE [%]
●The calculated load value at the moment a malfunction is detected is displayed.
COOLANT TEMP [°C]
or [°F]
●The engine coolant temperature at the moment a malfunction is detected is displayed.
S-FUEL TRIM-B1 [%]
●“Short-term fuel trim” at the moment a malfunction is detected is displayed.
●The short-term fuel trim indicates dynamic or instantaneous feedback compensation to the base fuel
schedule.
L-FUEL TRIM-B1 [%]
●“Long-term fuel trim” at the moment a malfunction is detected is displayed.
●The long-term fuel trim indicates much more gradual feedback compensation to the base fuel schedule
than short-term fuel trim.
ENGINE SPEED
[rpm]
●The engine speed at the moment a malfunction is detected is displayed.
VHCL SPEED [km/h]
or [mph]
●The vehicle speed at the moment a malfunction is detected is displayed.
B/FUEL SCHDL
[msec]
●The base fuel schedule at the moment a malfunction is detected is displayed.
INT/A TEMP SE [°C]
or [°F]
●The intake air temperature at the moment a malfunction is detected is displayed.