2001 NISSAN X-TRAIL OBD port

ENGINE CONTROL SYSTEM
EC-37
[QR25(WITH EURO-OBD)]
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Fuel Cut Control (at No Load and High Engine Speed)EBS00M0F
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-33
.
CAN CommunicationEBS00NBI
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

EC-40
[QR25(WITH EURO-OBD)]
BASIC SERVICE PROCEDURE
Learning will be cancelled if any of the following conditions are missed for even a moment.
●Battery voltage: More than 12.9V (At idle)
●Engine coolant temperature: 70 - 100°C (158 - 212°F)
●PNP switch: ON
●Electric load switch: OFF
(Air conditioner, headlamp, rear window defogger)
On vehicles equipped with daytime light systems, set lighting switch to the 1st position to light
only small lamps.
●Steering wheel: Neutral (Straight-ahead position)
●Vehicle speed: Stopped
●Transmission: Warmed-up
For A/T models with CONSULT-II, drive vehicle until “FLUID TEMP SE” in “DATA MONITOR” mode of “A/
T” system indicates less than 0.9V.
For A/T models without CONSULT-II and M/T models, drive vehicle for 10 minutes.
OPERATION PROCEDURE
With CONSULT-II
1. Perform EC-39, "Accelerator Pedal Released Position Learning" .
2. Perform EC-39, "
Throttle Valve Closed Position Learning" .
3. Start engine and warm it up to normal operating temperature.
4. Check that all items listed under the topic “PREPARATION” (previously mentioned) are in good order.
5. Select “IDLE AIR VOL LEARN” in “WORK SUPPORT” mode.
6. Touch “START” and wait 20 seconds.
7. Make sure that “CMPLT” is displayed on CONSULT-II screen. If
“CMPLT” is not displayed, “Idle Air Volume Learning” will not be
carried out successfully. In this case, find the cause of the inci-
dent by referring to the “DIAGNOSTIC PROCEDURE” below.
8. Rev up the engine two or three times and make sure that idle
speed and ignition timing are within the specifications.
SEF452Y
SEF454Y
ITEM SPECIFICATION
MBIB0238E

EC-42
[QR25(WITH EURO-OBD)]
BASIC SERVICE PROCEDURE
It is useful to perform E C - 111, "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 CheckEBS00M0L
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-42, "
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-48
[QR25(WITH EURO-OBD)]
ON BOARD DIAGNOSTIC (OBD) SYSTEM
If a 1st trip DTC is stored in the ECM, the time data will be “[1t]”.
FREEZE FRAME DATA AND 1ST TRIP FREEZE FRAME DATA
The ECM records the driving conditions such as fuel system status, calculated load value, engine coolant tem-
perature, short term fuel trim, long term fuel trim, engine speed, vehicle speed, base fuel schedule and intake
air temperature at the moment a malfunction is detected.
Data which are stored in the ECM memory, along with the 1st trip DTC, are called 1st trip freeze frame data.
The data, stored together with the DTC data, are called freeze frame data and displayed on CONSULT-II or
GST. The 1st trip freeze frame data can only be displayed on the CONSULT-II screen, not on the GST. For
details, see EC-97
.
Only one set of freeze frame data (either 1st trip freeze frame data or freeze frame data) can be stored in the
ECM. 1st trip freeze frame data is stored in the ECM memory along with the 1st trip DTC. There is no priority
for 1st trip freeze frame data and it is updated each time a different 1st trip DTC is detected. However, once
freeze frame data (2nd trip detection/MI on) is stored in the ECM memory, 1st trip freeze frame data is no
longer stored. Remember, only one set of freeze frame data can be stored in the ECM. The ECM has the fol-
lowing priorities to update the data.
For example, the EGR malfunction (Priority: 2) was detected and the freeze frame data was stored in the 2nd
trip. After that when the misfire (Priority: 1) is detected in another trip, the freeze frame data will be updated
from the EGR malfunction to the misfire. The 1st trip freeze frame data is updated each time a different mal-
function is detected. There is no priority for 1st trip freeze frame data. However, once freeze frame data is
stored in the ECM memory, 1st trip freeze data is no longer stored (because only one freeze frame data or 1st
trip freeze frame data can be stored in the ECM). If freeze frame data is stored in the ECM memory and freeze
frame data with the same priority occurs later, the first (original) freeze frame data remains unchanged in the
ECM memory.
Both 1st trip freeze frame data and freeze frame data (along with the DTCs) are cleared when the ECM mem-
ory is erased. Procedures for clearing the ECM memory are described in EC-56, "
HOW TO ERASE EMIS-
SION-RELATED DIAGNOSTIC INFORMATION" .
SYSTEM READINESS TEST (SRT) CODE
System Readiness Test (SRT) code is specified in Mode 1 of ISO 15031-5.
As part of an enhanced emissions test for Inspection & Maintenance (I/M), certain states require the status of
SRT be used to indicate whether the ECM has completed self-diagnosis of major emission systems and com-
ponents. Completion must be verified in order for the emissions inspection to proceed.
If a vehicle is rejected for a State emissions inspection due to one or more SRT items indicating “INCMP”, use
the information in this Service Manual to set the SRT to “CMPLT”.
In most cases the ECM will automatically complete its self-diagnosis cycle during normal usage, and the SRT
status will indicate “CMPLT” for each application system. Once set as “CMPLT”, the SRT status remains
“CMPLT” until the self-diagnosis memory is erased.
Occasionally, certain portions of the self-diagnostic test may not be completed as a result of the customer's
normal driving pattern; the SRT will indicate “INCMP” for these items.
NOTE:
The SRT will also indicate “INCMP” if the self-diagnosis memory is erased for any reason or if the ECM mem-
ory power supply is interrupted for several hours.
PBIB0911E
Priority Items
1Freeze frame data Misfire — DTC: P0300 - P0304
Fuel Injection System Function — DTC: P0171, P0172
2 Except the above items (Includes A/T related items)
3 1st trip freeze frame data

ON BOARD DIAGNOSTIC (OBD) SYSTEM
EC-49
[QR25(WITH EURO-OBD)]
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EC
If, during the state emissions inspection, the SRT indicates “CMPLT” for all test items, the inspector will con-
tinue with the emissions test. However, if the SRT indicates “INCMP” for one or more of the SRT items the
vehicle is returned to the customer untested.
NOTE:
If MI is “ON” during the state emissions inspection, the vehicle is also returned to the customer untested even
though the SRT indicates “CMPLT” for all test items. Therefore, it is important to check SRT (“CMPLT”) and
DTC (No DTCs) before the inspection.

TROUBLE DIAGNOSIS
EC-67
[QR25(WITH EURO-OBD)]
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TROUBLE DIAGNOSISPFP:00004
Trouble Diagnosis IntroductionEBS00M0S
INTRODUCTION
The engine has an ECM to control major systems such as fuel con-
trol, ignition control, idle air control system, etc. The ECM accepts
input signals from sensors and instantly drives actuators. It is essen-
tial that both input and output signals are proper and stable. At the
same time, it is important that there are no malfunctions such as vac-
uum leaks, fouled spark plugs, 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 GST) or a circuit tester connected should
be performed. Follow the “Work Flow” on EC-68
.
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 EC-70
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
SEF233G
SEF234G

TROUBLE DIAGNOSIS
EC-69
[QR25(WITH EURO-OBD)]
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Description for Work Flow
DIAGNOSTIC WORKSHEET
Description
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 a problem. It is
important to fully understand the symptoms or conditions for a cus-
tomer complaint.
Utilize a diagnostic worksheet like the one on the next page in order
to organize all the information for troubleshooting.
Some conditions may cause the MI to come on steady or blink and
DTC to be detected. Examples:
●Vehicle ran out of fuel, which caused the engine to misfire.
STEP DESCRIPTION
STEP IGet detailed information about the conditions and the environment when the incident/symptom occurred using the
“DIAGNOSTIC WORK SHEET”, EC-69
.
STEP IIBefore confirming the concern, check and write down (print out using CONSULT-II or GST) the (1st trip) DTC and the
(1st trip) freeze frame data, then erase the DTC and the data. (Refer to EC-56
.) The (1st trip) DTC and the (1st trip)
freeze frame data can be used when duplicating the incident at STEP III & IV.
If the incident cannot be verified, perform EC-115, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
Study the relationship between the cause, specified by (1st trip) DTC, and the symptom described by the customer.
(The “Symptom Matrix Chart” will be useful. See EC-77
.)
Also check related service bulletins for information.
STEP IIITry to confirm the symptom and under what conditions the incident occurs.
The “DIAGNOSTIC WORK SHEET” and the freeze frame data are 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-115, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
If the malfunction code is detected, skip STEP IV and perform STEP V.
STEP IVTry to detect the (1st trip) DTC by driving in (or performing) the “DTC Confirmation Procedure”. Check and read the
(1st trip) DTC and (1st trip) freeze frame data by using CONSULT-II or GST.
During the (1st trip) 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-115, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
In case the “DTC Confirmation Procedure” is not available, perform the “Overall Function Check” instead. The (1st
trip) 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 (1st trip) 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. (Refer to EC-73
.) Then perform inspections
according to the Symptom Matrix Chart. (Refer to EC-77
.)
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-819
, EC-106 .
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 “Circuit Inspection” in
GI-23, "
How to Perform Efficient Diagnosis for an Electrical Incident" .
Repair or replace the malfunction parts.
If malfunctioning part cannot be detected, perform EC-115, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCI-
DENT" .
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 No. P0000] is detected. If the incident
is still detected in the final check, perform STEP VI by using a method different from the previous one.
Before returning the vehicle to the customer, be sure to erase the unnecessary (already fixed) (1st trip) DTC in ECM
and TCM (Transmission control module). (Refer to EC-56, "
HOW TO ERASE EMISSION-RELATED DIAGNOSTIC
INFORMATION" and AT-39, "HOW TO ERASE DTC" .)
SEF907L

EC-94
[QR25(WITH EURO-OBD)]
TROUBLE DIAGNOSIS
: Average voltage for pulse signal (Actual pulse signal can be confirmed by oscilloscope.)
CONSULT-II FunctionEBS00M11
FUNCTION
107 Y/RIntake valve timing
control solenoid valve[Engine is running]
●Warm-up condition
●Idle speedBATTERY VOLTAGE
(11 - 14V)
[Engine is running]
●Warm-up condition
●When revving engine up to 2,000 rpm quicklyApproximately 4V - BATTERY
VOLTAGE (11 - 14V)
109
111W
WPower supply for
ECM[Ignition switch “ON”]BATTERY VOLTAGE
(11 - 14V)
11 2 W / RThrottle control motor
relay[Ignition switch “OFF”]BATTERY VOLTAGE
(11 - 14V)
[Ignition switch “ON”]0 - 1.0V
11 3 W / BThrottle control motor
relay power supply[Ignition switch “ON”]BATTERY VOLTAGE
(11 - 14V)
11 4 RThrottle control motor
(Open)[Ignition switch “ON”]
●Engine stopped
●Gear position is “D” (A/T model)
●Gear position is “1st” (M/T model)
●Accelerator pedal is depressing0 - 14V
11 5 B / YThrottle control motor
ground[Engine is running]
●Idle speedApproximately 0V
11 6 GThrottle control motor
(Close)[Ignition switch “ON”]
●Engine stopped
●Gear position is “D” (A/T model)
●Gear position is “1st” (M/T model)
●Accelerator pedal is releasing0 - 14V TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
PBIB0532E
PBIB0533E
PBIB0534E
Diagnostic test mode Function
Work supportThis mode enables a technician to adjust some devices faster and more accurately by following the
indications on the CONSULT-II unit.
Self-diagnostic resultsSelf-diagnostic results such as 1st trip DTC, DTCs and 1st trip freeze frame data or freeze frame data
can be read and erased quickly.*1
Data monitor Input/Output data in the ECM can be read.
Data monitor (SPEC)Input/Output of the specification for Basic fuel schedule, AFM, A/F feedback control value and the
other data monitor items can be read.
Active testDiagnostic Test Mode in which CONSULT-II drives some actuators apart from the ECMs and also
shifts some parameters in a specified range.
DTC & SRT confirmation The status of system monitoring tests and the self-diagnosis status/result can be confirmed.