2001 NISSAN X-TRAIL OBD port

TROUBLE DIAGNOSIS
EC-1147
[QR20(WITHOUT EURO-OBD)]
C
D
E
F
G
H
I
J
K
L
MA
EC
TROUBLE DIAGNOSISPFP:00004
Trouble Diagnosis IntroductionEBS00N3W
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 incident that occurs intermit-
tently 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-1148
.
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-1150
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-1149
[QR20(WITHOUT EURO-OBD)]
C
D
E
F
G
H
I
J
K
L
MA
EC
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 an incident. 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-1149
.
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-1142
.) 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-1192, "
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-1156
.)
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-1192, "
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-1192, "
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-1152
.) Then perform inspections
according to the Symptom Matrix Chart. (Refer to EC-1156
.)
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-1166
, EC-1182 .
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-1192, "
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.
(Refer to EC-1142, "
HOW TO ERASE EMISSION-RELATED DIAGNOSTIC INFORMATION" .)
SEF907L

TROUBLE DIAGNOSIS
EC-1173
[QR20(WITHOUT EURO-OBD)]
C
D
E
F
G
H
I
J
K
L
MA
EC
: Average voltage for pulse signal (Actual pulse signal can be confirmed by oscilloscope.)
CONSULT-II FunctionEBS00N45
FUNCTION
*1 The following emission-related diagnostic information is cleared when the ECM memory is erased.
1. Diagnostic trouble codes
2. 1st trip diagnostic trouble codes
3. Freeze frame data
4. 1st trip freeze frame data
5. Others11 5 B / YThrottle control motor
ground[Engine is running]
●Idle speedApproximately 0V
11 6 GThrottle control motor
(Close)[Ignition switch “ON”]
●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)
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.
Function test This mode is used to inform customers when their vehicle condition requires periodic maintenance.
ECM part number ECM part number can be read.

EC-1174
[QR20(WITHOUT EURO-OBD)]
TROUBLE DIAGNOSIS
ENGINE CONTROL COMPONENT PARTS/CONTROL SYSTEMS APPLICATION
X: Applicable
*1: This item includes 1st trip DTCs.
*2: This mode includes 1st trip freeze frame data or freeze frame data. The items appear on CONSULT-II screen in freeze frame data
mode only if a 1st trip DTC or DTC is detected. For details, refer to EC-1142
.
CONSULT-II INSPECTION PROCEDURE
1. Turn ignition switch OFF.
ItemDIAGNOSTIC TEST MODE
WORK
SUPPORTSELF-DIAGNOSTIC
RESULTS
DATA
MONI-
TORDATA
MONI-
TOR
(SPEC)ACTIVE
TEST
DTC*1FREEZE
FRAME
DATA*2
ENGINE CONTROL COMPONENT PARTS
INPUT
Crankshaft position sensor (POS)××××
Camshaft position sensor (PHASE)×
Mass air flow sensor×××
Engine coolant temperature sensor×××××
Heated oxygen sensor 1×××
Heated oxygen sensor 2××
Wheel sensor (Vehicle speed signal)××××
Accelerator pedal position sensor×××
Throttle position sensor×××
Intake air temperature sensor××
Knock sensor×
Refrigerant pressure sensor××
Ignition switch (start signal)××
Closed throttle position switch (accelera-
tor pedal position sensor signal)××
Air conditioner switch××
Park/neutral position (PNP) switch××
Stop lamp switch×××
Power steering pressure sensor×××
Battery voltage××
Load signal××
ENGINE CONTROL COMPONENT PARTS
OUTPUT
Injectors×× ×
Power transistor (Ignition timing)×× ×
Throttle control motor relay×××
EVAP canister purge volume control sole-
noid valve×× ×
Air conditioner relay××
Fuel pump relay××××
Cooling fan relay××××
Heated oxygen sensor 1 heater××
Heated oxygen sensor 2 heater××
Intake valve timing control solenoid valve×× ×
Calculated load value×××

TROUBLE DIAGNOSIS
EC-1175
[QR20(WITHOUT EURO-OBD)]
C
D
E
F
G
H
I
J
K
L
MA
EC
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-1177
[QR20(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
SIG-
NALSMAIN
SIG-
NALSCAN
DIAG
SUP-
PORT
MNTRDescription Remarks
ENG SPEED [rpm]××
●Indicates the engine speed computed
from the signals of the crankshaft posi-
tion sensor (POS) and camshaft posi-
tion 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.
COOLAN TEMP/S
[°C] or [°F]××
●The engine coolant temperature (deter-
mined by the signal voltage of the
engine coolant temperature 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 heated oxygen
sensor 1 is displayed.
HO2S2 (B1) [V]××
●The signal voltage of heated oxygen
sensor 2 is displayed.
HO2S1 MNTR (B1)
[RICH/LEAN]××
●Display of heated oxygen sensor 1 sig-
nal during air-fuel ratio feedback control:
RICH ... means the mixture became
“rich”, and control is being affected
toward a leaner mixture.
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 sig-
nal:
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 dis-
played.
ACCEL SEN 1 [V]××
●The accelerator pedal position sensor
signal voltage is displayed.
ACCEL SEN 2 [V]×
THRTL SEN 1 [V]××
●The throttle position sensor signal volt-
age is displayed.
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 sensor) is indicated.
START SIGNAL
[ON/OFF]××
●Indicates [ON/OFF] condition from the
starter signal.●After starting the engine, [OFF] is
displayed regardless of the starter
signal.

EC-1178
[QR20(WITHOUT EURO-OBD)]
TROUBLE DIAGNOSIS
CLSD THL POS
[ON/OFF]××●Indicates idle position [ON/OFF] com-
puted by ECM according to the acceler-
ator pedal position sensor signal.
AIR COND SIG
[ON/OFF]××
●Indicates [ON/OFF] condition of the air
conditioner switch as determined by the
air conditioner signal.
P/N POSI SW
[ON/OFF]××
●Indicates [ON/OFF] condition from the
park/neutral position (PNP) switch sig-
nal.
PW/ST SIGNAL
[ON/OFF]××
●[ON/OFF] condition of the power steer-
ing system (determined by the signal
voltage of the power steering 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 posi-
tion.
OFF ... Both rear window defogger
switch and lighting switch are OFF.
IGNITION SW
[ON/OFF]××
●Indicates [ON/OFF] condition from igni-
tion 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.
B/FUEL SCHDL
[msec]×
●“Base fuel schedule” indicates the fuel
injection pulse width programmed into
ECM, prior to any learned on board cor-
rection.
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.
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.
CAL/LD VALUE [%]
●“Calculated load value” indicates the
value of the current airflow divided by
peak airflow.
MASS AIRFLOW
[g·m/s]
●Indicates the mass airflow computed by
ECM according to the signal voltage of
the mass air flow sensor.
PURG VOL C/V
[%]
●Indicates the EVAP canister purge vol-
ume control solenoid valve control value
computed by the ECM according to the
input signals.
●The opening becomes larger as the
value increases. Monitored item
[Unit]ECM
INPUT
SIG-
NALSMAIN
SIG-
NALSCAN
DIAG
SUP-
PORT
MNTRDescription Remarks

TROUBLE DIAGNOSIS
EC-1179
[QR20(WITHOUT EURO-OBD)]
C
D
E
F
G
H
I
J
K
L
MA
ECINT/V TIM (B1)
[°CA]●Indicates [°CA] of intake camshaft
advanced angle.
INT/V SOL (B1) [%]
●The control condition of the intake valve
timing control solenoid valve (deter-
mined by ECM according to the input
signals) is indicated.
ON ... intake valve timing control is oper-
ating.
OFF ... Intake valve timing control is not
operating.
AIR COND RLY
[ON/OFF]×
●The air conditioner relay control condi-
tion (determined by ECM according to
the input signals) is indicated.
FUEL PUMP RLY
[ON/OFF]×
●Indicates the fuel pump relay control
condition determined by ECM according
to the input signals.
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
(determined 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 performed yet.
CMPLT ... Idle air volume learning has
already been performed successfully.
TRVL AFTER MIL
[km] or [mile]
●Distance traveled while MI is activated.
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
SIG-
NALSMAIN
SIG-
NALSCAN
DIAG
SUP-
PORT
MNTRDescription Remarks