sensor oxygen NISSAN X-TRAIL 2001 Service Repair Manual

EC-1044
[QR20(WITH EURO-OBD)]
DTC P1147 HO2S2
Procedure for COND2
1. While driving, release accelerator pedal completed with “OD”
OFF (A/T models only) from the above condition [step 8] until
“INCOMPLETE” at “COND2” on CONSULT-II screen has turned
to “COMPLETED” (It will take approximately 4 seconds.)
NOTE:
If “COMPLETE” already appears at “COND3” on CONSULT-
II screen before “Procedure for COND3” is conducted, it is
unnecessary to conduct step 1 in “Procedure for COND3”.
Procedure for COND3
1. Stop vehicle and let it idle until “INCOMPLETE” of “COND3” on
CONSULT-II screen has turned to “COMPLETED”. (It will take a
maximum of approximately 6 minutes.)
2. Make sure that “OK” is displayed after touching “SELF-DIAG
RESULTS”.
If “NG” is displayed, refer to EC-1046, "
Diagnostic Procedure" .
Overall Function CheckEBS00N0T
Use this procedure to check the overall function of the heated oxygen sensor 2 circuit. During this check, a
DTC might not be confirmed.
WITH GST
1. Start engine and drive vehicle at a speed of more than 70 km/h (43 MPH) for 2 consecutive minutes.
2. Stop vehicle with engine running.
3. Set voltmeter probes between ECM terminal 95 (HO2S2 signal) and engine ground.
4. Check the voltage when revving up to 4,000 rpm under no load
at least 10 times.
(Depress and release accelerator pedal as soon as possible.)
The voltage should be above 0.68V at least once during this
procedure.
If the voltage can be confirmed in step 4, step 5 is not nec-
essary.
5. Keep vehicle idling for 10 minutes, then check the voltage. Or
check the voltage when coasting from 80 km/h (50 MPH) in “D”
position with “OD” OFF (A/T), 3rd gear position (M/T).
The voltage should be above 0.68V at least once during this
procedure.
6. If NG, go to EC-1046, "
Diagnostic Procedure" .
PBIB0558E
SEC778C
PBIB0550E

DTC P1147 HO2S2
EC-1047
[QR20(WITH EURO-OBD)]
C
D
E
F
G
H
I
J
K
L
MA
EC
3.CHECK HO2S2 GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch “OFF”.
2. Disconnect heated oxygen sensor 2 harness connector.
3. Check harness continuity between HO2S2 terminal 3 and
engine 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 power in harness or con-
nectors.
4.CHECK HO2S2 INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Disconnect ECM harness connector.
2. Check harness continuity between ECM terminal 95 and HO2S2 terminal 2.
Refer to Wiring Diagram.
3. Check harness continuity between ECM terminal 95 or HO2S2 terminal 2 and ground.
Refer to Wiring Diagram.
4. Also check harness for short to ground or short to power.
OK or NG
OK >> GO TO 5.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
5.CHECK HEATED OXYGEN SENSOR 2
Refer to EC-1047, "
Component Inspection" .
OK or NG
OK >> GO TO 6.
NG >> Replace heated oxygen sensor 2.
6.CHECK INTERMITTENT INCIDENT
Refer to EC-847, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
>>INSPECTION END
Component InspectionEBS00N0W
HEATED OXYGEN SENSOR 2
With CONSULT-II
1. Start engine and drive vehicle at a speed of more than 70 km/h (43 MPH) for 2 consecutive minutes.
2. Stop vehicle with engine running.Continuity should exist.
PBIB0500E
Continuity should exist.
Continuity should not exist.

EC-1048
[QR20(WITH EURO-OBD)]
DTC P1147 HO2S2
3. Select “FUEL INJECTION” in “ACTIVE TEST” mode, and select
“HO2S2 (B1)” as the monitor item with CONSULT-II.
4. Check “HO2S2 (B1)” at idle speed when adjusting “FUEL INJECTION” to ±25%.
“HO2S2 (B1)” should be above 0.68V at least once when the “FUEL INJECTION” is +25%.
“HO2S2 (B1)” should be below 0.50V at least once when the “FUEL INJECTION” is −25%.
CAUTION:
●Discard any heated oxygen sensor which has been dropped from a height of more than 0.5 m
(19.7 in) onto a hard surface such as a concrete floor; use a new one.
●Before installing new oxygen sensor, clean exhaust system threads using Oxygen Sensor
Thread Cleaner tool J-43897-18 or J-43897-12 and approved anti-seize lubricant.
Without CONSULT-II
1. Start engine and drive vehicle at a speed of more than 70 km/h (43 MPH) for 2 consecutive minutes.
2. Stop vehicle with engine running.
3. Set voltmeter probes between ECM terminal 95 (HO2S2 signal) and engine ground.
4. Check the voltage when revving up to 4,000 rpm under no load
at least 10 times.
(Depress and release accelerator pedal as soon as possible.)
The voltage should be above 0.68V at least once during this
procedure.
If the voltage is above 0.68V at step 4, step 5 is not neces-
sary.
5. Keep vehicle idling for 10 minutes, then check voltage. Or check
the voltage when coasting from 80 km/h (50 MPH) in “D” posi-
tion with “OD” OFF (A/T), 3rd gear position (M/T).
The voltage should be below 0.50V at least once during this
procedure.
6. If NG, replace heated oxygen sensor 2.
CAUTION:
●Discard any heated oxygen sensor which has been dropped from a height of more than 0.5 m (19.7
in) onto a hard surface such as a concrete floor; use a new one.
●Before installing new oxygen sensor, clean exhaust system threads using Oxygen Sensor Thread
Cleaner tool J-43897-18 or J-43897-12 and approved anti-seize lubricant.
Removal and InstallationEBS00N0X
HEATED OXYGEN SENSOR 2
Refer to EX-2, "EXHAUST SYSTEM" .
SEF662Y
PBIB0551E
PBIB0550E

SERVICE DATA AND SPECIFICATIONS (SDS)
EC-1117
[QR20(WITH EURO-OBD)]
C
D
E
F
G
H
I
J
K
L
MA
EC
SERVICE DATA AND SPECIFICATIONS (SDS)PFP:00030
Fuel PressureEBS00N2T
Idle Speed and Ignition TimingEBS00N2U
*1: Under the following conditions:
●Air conditioner switch: OFF
●Electric load: OFF (Lights, heater fan & rear window defogger)
●Steering wheel: Kept in straight-ahead position
*2: It refrigerant pressure is low, the idle speed may not be increased.
Calculated Load ValueEBS00N2V
Mass Air Flow SensorEBS00N2W
*: Engine is warmed up to normal operating temperature and running under no-load.
Intake Air Temperature SensorEBS00N2X
Engine Coolant Temperature SensorEBS00N2Y
Heated Oxygen Sensor 1 HeaterEBS00N2Z
Heated Oxygen sensor 2 HeaterEBS00N30
Crankshaft Position Sensor (POS)EBS00N31
Refer to EC-961, "Component Inspection" .
Camshaft Position Sensor (PHASE)EBS00N32
Refer to EC-967, "Component Inspection" .
Fuel pressure at idle kPa (bar, kg/cm2 , psi)Approximately 350 (3.5, 3.57, 51)
Target idle speed
No-load*1 (in “P” or N” position)A/T: 700±50 rpm
M/T: 650±50 rpm
Air conditioner: ONIn “P” or N” position
725 rpm or more*
2
Ignition timingIn “P” or N” position AT: 16°±5° BTDC
MT: 14°±5° BTDC
Calculated load value% (Using CONSULT-II or GST)
At idle10 - 35
At 2,500 rpm10 - 35
Supply voltageBattery voltage (11 - 14V)
Output voltage at idle1.1 - 1.5*V
Mass air flow (Using CONSULT-II or GST)1.4 - 4.0 g·m/sec at idle*
4.0 - 10.0 g·m/sec at 2,500 rpm*
Temperature °C (°F) Resistance kΩ
25 (77)1.9 - 2.1
80 (176)0.31 - 0.37
Temperature °C (°F) Resistance kΩ
20 (68) 2.1 - 2.9
50 (122) 0.68 - 1.00
90 (194) 0.236 - 0.260
Resistance [at 25°C (77°F)] 2.3 - 4.3Ω
Resistance [at 25°C (77°F)] 2.3 - 4.3Ω

PREPARATION
EC-1125
[QR20(WITHOUT EURO-OBD)]
C
D
E
F
G
H
I
J
K
L
MA
EC
PREPARATIONPFP:00002
Special Service ToolsEBS00N3C
The actual shapes of Kent-Moore tools may differ from those of special service tools illustrated here.
Commercial Service ToolsEBS00N3D
Tool number
Tool nameDescription
KV10117100
Heated oxygen
sensor wrenchLoosening or tightening heated oxygen sensors
with 22 mm (0.87 in) hexagon nut
KV10114400
Heated oxygen
sensor wrenchLoosening or tightening heated oxygen sensors
a: 22 mm (0.87 in)
S-NT379
S-NT636
Tool name Description
Quick connector
releaseRemoving fuel tube quick connectors in engine
room
(Available in SEC. 164 of PARTS CATALOG:
Part No. 16441 6N210)
Fuel filler cap adapter Checking fuel tank vacuum relief valve opening
pressure
Socket wrench Removing and installing engine coolant
temperature sensor
PBIC0198E
S-NT653
S-NT705

EC-1126
[QR20(WITHOUT EURO-OBD)]
PREPARATION
Oxygen sensor thread
cleanerReconditioning the exhaust system threads
before installing a new oxygen sensor. Use with
anti-seize lubricant shown below.
a: 18 mm diameter with pitch 1.5 mm for
Zirconia Oxygen Sensor
b: 12 mm diameter with pitch 1.25 mm for
Titania Oxygen Sensor
Anti-seize lubricant
(Permatex
TM 133AR
or equivalent meeting
MIL specification MIL-
A-907)Lubricating oxygen sensor thread cleaning tool
when reconditioning exhaust system threads. Tool name Description
AEM488
S-NT779

ENGINE CONTROL SYSTEM
EC-1129
[QR20(WITHOUT EURO-OBD)]
C
D
E
F
G
H
I
J
K
L
MA
EC
System ChartEBS00N3G
*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) SystemEBS00N3H
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
functionActuator
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 *
1Density of oxygen in exhaust gas
ESP/TCS/ABS control unit *
2ESP/TCS operation command
Wheel sensor Vehicle speed
Air conditioner switch Air conditioner operation

EC-1130
[QR20(WITHOUT EURO-OBD)]
ENGINE CONTROL SYSTEM
SYSTEM DESCRIPTION
The amount of fuel injected from the fuel injector is determined by the ECM. The ECM controls the length of
time the valve remains open (injection pulse duration). The amount of fuel injected is a program value in the
ECM memory. The program value is preset by engine operating conditions. These conditions are determined
by input signals (for engine speed and intake air) from both the crankshaft position sensor and the mass air
flow sensor.
VARIOUS FUEL INJECTION INCREASE/DECREASE COMPENSATION
In addition, the amount of fuel injected is compensated to improve engine performance under various operat-
ing conditions as listed below.

●During warm-up
●When starting the engine
●During acceleration
●Hot-engine operation
●When selector lever is changed from “N” to “D”
●High-load, high-speed operation

●During deceleration
●During high engine speed operation
MIXTURE RATIO FEEDBACK CONTROL (CLOSED LOOP CONTROL)
The mixture ratio feedback system provides the best air-fuel mixture ratio for driveability and emission control.
The three way catalyst (manifold) can then better reduce CO, HC and NOx emissions. This system uses
heated oxygen sensor 1 in the exhaust manifold to monitor if the engine operation is rich or lean. The ECM
adjusts the injection pulse width according to the sensor voltage signal. For more information about heated
oxygen sensor 1, refer to EC-1229
. This maintains the mixture ratio within the range of stoichiometric (ideal
air-fuel mixture).
This stage is referred to as the closed loop control condition.
Heated oxygen sensor 2 is located downstream of the three way catalyst (manifold). Even if the switching
characteristics of heated oxygen sensor 1 shift, the air-fuel ratio is controlled to stoichiometric by the signal
from heated oxygen sensor 2.
Open Loop Control
The open loop system condition refers to when the ECM detects any of the following conditions. Feedback
control stops in order to maintain stabilized fuel combustion.
●Deceleration and acceleration
●High-load, high-speed operation
●Malfunction of heated oxygen sensor 1 or its circuit
●Insufficient activation of heated oxygen sensor 1 at low engine coolant temperature
●High engine coolant temperature
●During warm-up
●After shifting from “N” to “D”
●When starting the engine
PBIB0121E

ENGINE CONTROL SYSTEM
EC-1131
[QR20(WITHOUT EURO-OBD)]
C
D
E
F
G
H
I
J
K
L
MA
EC
MIXTURE RATIO SELF-LEARNING CONTROL
The mixture ratio feedback control system monitors the mixture ratio signal transmitted from heated oxygen
sensor 1. This feedback signal is then sent to the ECM. The ECM controls the basic mixture ratio as close to
the theoretical mixture ratio as possible. However, the basic mixture ratio is not necessarily controlled as orig-
inally designed. Both manufacturing differences (i.e., mass air flow sensor hot film) and characteristic changes
during operation (i.e., injector clogging) directly affect mixture ratio.
Accordingly, the difference between the basic and theoretical mixture ratios is monitored in this system. This is
then computed in terms of “injection pulse duration” to automatically compensate for the difference between
the two ratios.
“Fuel trim” refers to the feedback compensation value compared against the basic injection duration. Fuel trim
includes short term fuel trim and long term fuel trim.
“Short term fuel trim” is the short-term fuel compensation used to maintain the mixture ratio at its theoretical
value. The signal from heated oxygen sensor 1 indicates whether the mixture ratio is RICH or LEAN compared
to the theoretical value. The signal then triggers a reduction in fuel volume if the mixture ratio is rich, and an
increase in fuel volume if it is lean.
“Long term fuel trim” is overall fuel compensation carried out long-term to compensate for continual deviation
of the short term fuel trim from the central value. Such deviation will occur due to individual engine differences,
wear over time and changes in the usage environment.
FUEL INJECTION TIMING
Two types of systems are used.
Sequential Multiport Fuel Injection System
Fuel is injected into each cylinder during each engine cycle according to the firing order. This system is used
when the engine is running.
Simultaneous Multiport Fuel Injection System
Fuel is injected simultaneously into all four cylinders twice each engine cycle. In other words, pulse signals of
the same width are simultaneously transmitted from the ECM.
The four injectors will then receive the signals two times for each engine cycle.
This system is used when the engine is being started and/or if the fail-safe system (CPU) is operating.
FUEL SHUT-OFF
Fuel to each cylinder is cut off during deceleration or operation of the engine at excessively high speeds.
SEF337W

EC-1144
[QR20(WITHOUT EURO-OBD)]
ON BOARD DIAGNOSTIC (OBD) SYSTEM
Malfunction Indicator (MI)
EBS00N3V
DESCRIPTION
The MI is located on the instrument panel.
1. The MI will light up when the ignition switch is turned ON without
the engine running. This is a bulb check.
●If the MI does not light up, refer to DI-43, "WARNING LAMPS" ,
or see EC-1265
.
2. When the engine is started, the MI should go off.
If the MI remains on, the on board diagnostic system has
detected an engine system malfunction.
ON BOARD DIAGNOSTIC SYSTEM FUNCTION
The on board diagnostic system has the following four functions.
MI Flashing without DTC
If the ECM is in Diagnostic Test Mode II, MI may flash when engine is running. In this case, check ECM diag-
nostic test mode. EC-1145, "
HOW TO SWITCH DIAGNOSTIC TEST MODE" .
How to switch the diagnostic test (function) modes, and details of the above functions are described later EC-
11 4 5 .
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
SAT652J
Diagnostic Test
ModeKEY and ENG.
Sta tusFunction Explanation of Function
Mode I Ignition switch in
“ON” position
Engine stoppedBULB CHECK This function checks the MI bulb for damage (blown, open
circuit, etc.).
If the MI does not come on, check MI circuit.
Engine running MALFUNCTION
WARNINGThis is a usual driving condition. When a malfunction is
detected twice in two consecutive driving cycles (two trip
detection logic), the MI will light up to inform the driver that
a malfunction has been detected.
The following malfunctions will light up the MI in the 1st
trip.
●“One trip detection diagnoses”
Mode II Ignition switch in
“ON” position
Engine stoppedSELF-DIAGNOSTIC
RESULTSThis function allows DTCs and 1st trip DTCs to be read.
Engine running HEATED OXYGEN SENSOR 1
MONITORThis function allows the fuel mixture condition (lean or
rich), monitored by heated oxygen sensor 1, to be read.