2001 NISSAN X-TRAIL sensor oxygen

EC-96
[QR25(WITH EURO-OBD)]
TROUBLE DIAGNOSIS
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-48
.
CONSULT-II INSPECTION PROCEDURE
1. Turn ignition switch OFF.
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”.
ENGINE CONTROL COMPONENT PARTS
OUTPUT
Injectors×× ×
Power transistor (Ignition timing)×× ×
Throttle control motor relay×××
EVAP canister purge volume con-
trol solenoid 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×××
VIAS control solenoid valve×× × ItemDIAGNOSTIC TEST MODE
WORK
SUP-
PORTSELF-DIAGNOSTIC
RESULTS
DATA
MONI-
TORDATA
MONI-
TOR
(SPEC)ACTIVE
TESTDTC & SRT
CONFIRMATION
DTC*1FREEZE
FRAME
DATA*2SRT
STATUSDTC
WORK
SUP-
PORT
PBIB0376E
MBIB0233E

TROUBLE DIAGNOSIS
EC-97
[QR25(WITH EURO-OBD)]
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EC
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
*: 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-20, "INDEX FOR DTC" .)
Freeze Frame Data and 1st Trip Freeze Frame Data
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
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
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-20, "
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

EC-98
[QR25(WITH EURO-OBD)]
TROUBLE DIAGNOSIS
*1: The items are the same as those of 1st trip freeze frame data.
DATA MONITOR MODE
Monitored Item
×: Applicable 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. Freeze frame data
item*1Description
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 the heated oxygen
sensor 1 is displayed.
HO2S2 (B1) [V]××
●The signal voltage of the 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.

TROUBLE DIAGNOSIS
EC-99
[QR25(WITH EURO-OBD)]
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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.
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. Monitored item
[Unit]ECM
INPUT
SIG-
NALSMAIN
SIG-
NALSCAN
DIAG
SUP-
PORT
MNTRDescription Remarks

TROUBLE DIAGNOSIS
EC-101
[QR25(WITH EURO-OBD)]
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NOTE:
●Any monitored item that does not match the vehicle being diagnosed is deleted from the display automatically. 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-LOW
CAN COMM
[OK/NG]×
●Indicates the communication condition
of CAN communication line.●These items are not displayed in
“SELECTION FROM MENU”
mode. CAN CIRC 1
[OK/UNKWN]×
CAN CIRC 2
[OK/UNKWN]×
CAN CIRC 3
[OK/UNKWN]×
CAN CIRC 4
[OK/UNKWN]×
CAN CIRC 5
[OK/UNKWN]× Monitored item
[Unit]ECM
INPUT
SIG-
NALSMAIN
SIG-
NALSCAN
DIAG
SUP-
PORT
MNTRDescription Remarks

EC-102
[QR25(WITH EURO-OBD)]
TROUBLE DIAGNOSIS
DATA MONITOR (SPEC) MODE
Monitored Item
NOTE:
●Any monitored item that does not match the vehicle being diagnosed is deleted from the display automatically.
ACTIVE TEST MODE
Test Item
Monitored item [Unit]ECM
input
signalsMain
signalsDescription Remarks
ENG SPEED [rpm]×
●Indicates the engine speed computed
from the signals of the crankshaft posi-
tion sensor (POS) and camshaft position
sensor (PHASE).
MAS A/F SE-B1 [V]××
●The signal voltage of the mass air flow
sensor specification is displayed.●When engine is running specification
range is indicated.
B/FUEL SCHDL
[msec]
●“Base fuel schedule” indicates the fuel
injection pulse width programmed into
ECM, prior to any learned on board cor-
rection.
●When engine is running specification
range is indicated.
A/F ALPHA-B1 [%]×
●The mean value of the air-fuel ratio feed-
back correction factor per cycle is indi-
cated.●When engine is running specification
range is indicated.
●This data also includes the data for the
air-fuel ratio learning control.
TEST ITEM CONDITION JUDGEMENT CHECK ITEM (REMEDY)
FUEL INJEC-
TION
●Engine: Return to the original
trouble condition
●Change the amount of fuel injec-
tion using CONSULT-II.If trouble symptom disappears, see
CHECK ITEM.
●Harness and connectors
●Fuel injectors
●Heated oxygen sensor 1
IGNITION TIM-
ING
●Engine: Return to the original
trouble condition
●Timing light: Set
●Retard the ignition timing using
CONSULT-II.If trouble symptom disappears, see
CHECK ITEM.
●Perform “Idle Air Volume Learn-
ing”.
POWER BAL-
ANCE
●Engine: After warming up, idle
the engine.
●A/C switch “OFF”
●Shift lever “N”
●Cut off each injector signal one at
a time using CONSULT-II.Engine runs rough or dies.
●Harness and connectors
●Compression
●Fuel injectors
●Power transistor
●Spark plugs
●Ignition coils
COOLING FAN
●Ignition switch: ON
●Turn the cooling fan “ON” and
“OFF” with CONSULT-II.Cooling fan moves and stops.
●Harness and connectors
●Cooling fan relay
●Cooling fan motor
ENG COOLANT
TEMP
●Engine: Return to the original
trouble condition
●Change the engine coolant tem-
perature using CONSULT-II.If trouble symptom disappears, see
CHECK ITEM.
●Harness and connectors
●Engine coolant temperature sen-
sor
●Fuel injectors
FUEL PUMP
RELAY
●Ignition switch: ON (Engine
stopped)
●Turn the fuel pump relay “ON”
and “OFF” using CONSULT-II
and listen to operating sound.Fuel pump relay makes the operat-
ing sound.●Harness and connectors
●Fuel pump relay

EC-128
[QR25(WITH EURO-OBD)]
DTC P0031, P0032 HO2S1 HEATER
DTC P0031, P0032 HO2S1 HEATER
PFP:22690
DescriptionEBS00M1Q
SYSTEM DESCRIPTION
The ECM performs ON/OFF duty control of the heated oxygen sensor 1 heater corresponding to the engine
speed and engine coolant temperature. The duty percent varies with engine coolant temperature when engine
is started.
OPERATION
CONSULT-II Reference Value in Data Monitor ModeEBS00M1R
Specification data are reference values.
ECM Terminals and Reference ValueEBS00M1S
Specification data are reference values and are measured between each terminal and ground.
Pulse signal is measured by CONSULT-II.
CAUTION:
Do not use ECM ground terminals when measuring input/output voltage. Doing so may result in dam-
age to the ECM's transistor. Use a ground other than ECM terminals, such as the ground.
: Average voltage for pulse signal (Actual pulse signal can be confirmed by oscilloscope.) Sensor Input Signal to ECM ECM function Actuator
Camshaft position sensor (PHASE)
Crankshaft position sensor (POS)Engine speed
Heated oxygen sensor 1
heater controlHeated oxygen sensor 1 heater
Engine coolant temperature sensorEngine coolant tempera-
ture
Engine speed rpm Heated oxygen sensor 1 heater
Above 3,600 OFF
Below 3,600 after warming up ON
MONITOR ITEM CONDITION SPECIFICATION
HO2S1 HTR (B1)
●Engine: After warm up
●Engine speed: Below 3,600 rpmON
●Engine speed: Above 3,600 rpm OFF
TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
2P/LHeated oxygen sen-
sor 1 heater[Engine is running]
●Warm-up condition
●Engine speed is below 3,600 rpm.Approximately 7.0V
[Engine is running]
●Engine speed is above 3,600 rpm.BATTERY VOLTAGE
(11 - 14V)
PBIB0519E

DTC P0031, P0032 HO2S1 HEATER
EC-129
[QR25(WITH EURO-OBD)]
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On Board Diagnosis LogicEBS00M1T
DTC Confirmation ProcedureEBS00M1U
NOTE:
If “DTC Confirmation Procedure” has been previously conducted, always turn ignition switch “OFF” and wait at
least 10 seconds before conducting the next test.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is between 10.5V and 16V at
idle.
WITH CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Turn ignition switch “OFF” and wait at least 10 seconds.
3. Turn ignition switch “ON” and select “DATA MONITOR” mode
with CONSULT-II.
4. Start engine and run it for at least 6 seconds at idle speed.
5. If 1st trip DTC is detected, go to EC-131, "
Diagnostic Procedure"
.
WITH GST
1. Start engine and warm it up to normal operating temperature.
2. Turn ignition switch “OFF and wait at least 10 seconds.
3. Start engine and run it for at least 6 seconds at idle speed.
4. Turn ignition switch “OFF” and wait at least 10 seconds.
5. Start engine and run it for at least 6 seconds at idle speed.
6. Select “MODE 3” with GST.
7. If DTC is detected, go to EC-131, "
Diagnostic Procedure" .
●When using GST, “DTC Confirmation Procedure” should be performed twice as much as when
using CONSULT-II because GST cannot display MODE 7 (1st trip DTC) concerning this diagnosis.
Therefore, using CONSULT-II is recommended.
DTC No.Trouble diagnosis
nameDTC detecting condition Possible cause
P0031
0031Heated oxygen
sensor 1 heater
control circuit lowThe current amperage in the heated oxygen
sensor 1 heater circuit is out of the normal
range.
(An excessively low voltage signal is sent to
ECM through the heated oxygen sensor 1
heater.)
●Harness or connectors
(The heated oxygen sensor 1 heater circuit is
open or shorted.)
●Heater oxygen sensor 1 heater
P0032
0032Heated oxygen
sensor 1 heater
control circuit highThe current amperage in the heated oxygen
sensor 1 heater circuit is out of the normal
range.
(An excessively high voltage signal is sent to
ECM through the heated oxygen sensor 1
heater.)
●Harness or connectors
(The heated oxygen sensor 1 heater circuit is
shorted.)
●Heater oxygen sensor 1 heater
SEF058Y