2001 NISSAN X-TRAIL sensor oxygen

TROUBLE DIAGNOSIS
EC-489
[QR25(WITHOUT EURO-OBD)]
C
D
E
F
G
H
I
J
K
L
MA
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-1119, "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-1119, "
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-490
[QR25(WITHOUT 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 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.

TROUBLE DIAGNOSIS
EC-491
[QR25(WITHOUT EURO-OBD)]
C
D
E
F
G
H
I
J
K
L
MA
EC
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-493
[QR25(WITHOUT EURO-OBD)]
C
D
E
F
G
H
I
J
K
L
MA
EC
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-494
[QR25(WITHOUT 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 signal of the crankshaft position
sensor (POS).
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-534
[QR25(WITHOUT EURO-OBD)]
DTC P0134 HO2S1
DTC P0134 HO2S1
PFP:22690
Component DescriptionEBS00NFJ
The heated oxygen sensor 1 is placed into the exhaust manifold. It
detects the amount of oxygen in the exhaust gas compared to the
outside air. The heated oxygen sensor 1 has a closed-end tube
made of ceramic zirconia. The zirconia generates voltage from
approximately 1V in richer conditions to 0V in leaner conditions. The
heated oxygen sensor 1 signal is sent to the ECM. The ECM adjusts
the injection pulse duration to achieve the ideal air-fuel ratio. The
ideal air-fuel ratio occurs near the radical change from 1V to 0V.
CONSULT-II Reference Value in Data Monitor ModeEBS00NFK
Specification data are reference values.
ECM Terminals and Reference ValueEBS00NFL
Specification data are reference values and are measured between each terminal and ground.
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.
SEF463R
SEF288D
MONITOR ITEM CONDITION SPECIFICATION
HO2S1 (B1)
●Engine: After warming upMaintaining engine speed at 2,000
rpm0 - 0.3V ←→ Approx. 0.6 - 1.0V
HO2S1 MNTR (B1)
●Engine: After warming upMaintaining engine speed at 2,000
rpmLEAN ←→ RICH
Changes more than 5 times dur-
ing 10 seconds.
TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
92 G/WHeated oxygen sen-
sor 1[Engine is running]
●Warm-up condition
●Engine speed is 2,000 rpm.0 - Approximately 1.0V (Periodi-
cally change)

DTC P0134 HO2S1
EC-535
[QR25(WITHOUT EURO-OBD)]
C
D
E
F
G
H
I
J
K
L
MA
EC
On Board Diagnosis LogicEBS00NFM
Under the condition in which the heated oxygen sensor 1 signal is
not input, the ECM circuits will read a continuous approximately
0.3V. Therefore, for this diagnosis, the time that output voltage is
within 200 to 400 mV range is monitored, and the diagnosis checks
that this time is not inordinately long.
DTC Confirmation ProcedureEBS00NFN
Use this procedure to check the overall function of the heated oxygen sensor 1 circuit. During this check, a 1st
trip DTC might not be confirmed.
WITH CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Select “MANU TRIG” in “ATA MONITOR” mode with CONSULT-
II, and select “HO2S1 (B1)”.
3. Hold engine speed at 2,000 rpm under no load.
4. Make sure that the indications do not remain in the range
between 0.2 to 0.4V.
5. If NG, go to EC-537, "
Diagnostic Procedure" .
WITHOUT CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Set voltmeter probes between ECM terminal 92 (HO2S1signal) and engine ground.
3. Check the following with engine speed held at 2,000 rpm con-
stant under no load.
●The voltage does not remain in the range of 0.2 to 0.4V.
4. If NG, go to EC-537, "
Diagnostic Procedure" .
SEF237U
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0134
0134Heated oxygen sensor
1 circuit high no activity
detectedThe voltage from the sensor is constantly
approx. 0.3V.
●Harness or connectors
(The sensor circuit is open or shorted)
●Heated oxygen sensor 1
SEF646Y
PBIB0543E

DTC P0134 HO2S1
EC-537
[QR25(WITHOUT EURO-OBD)]
C
D
E
F
G
H
I
J
K
L
MA
EC
Diagnostic ProcedureEBS00NFQ
1.INSPECTION START
1. Turn ignition switch “OFF”.
2. Loosen and retighten engine ground screws.
>> GO TO 2.
2.CHECK HO2S1 GROUND CIRCUIT FOR OPEN AND SHORT
1. Disconnect HO2S1 harness connector.
2. Check harness continuity between HO2S1 terminal 3 and
ground.
Refer to Wiring Diagram.
3. Also check harness for short to power.
OK or NG
OK >> GO TO 3.
NG >> Repair open circuit or short to power in harness or con-
nectors.
3.CHECK HO2S1 INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Disconnect ECM harness connector.
2. Check harness continuity between ECM terminal 92 and HO2S1 terminal 2.
Refer to Wiring Diagram.
3. Check harness continuity between ECM terminal 92 or HO2S1 terminal 2 and ground.
Refer to Wiring Diagram.
4. Also check harness for short to power.
OK or NG
OK >> GO TO 4.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
4.CHECK HEATED OXYGEN SENSOR 1
Refer to EC-538, "
Component Inspection" .
OK or NG
OK >> GO TO 5.
NG >> Replace heated oxygen sensor 1.
PBIB0494E
Continuity should exist.
PBIB0500E
Continuity should exist.
Continuity should not exist.