2005 NISSAN X-TRAIL exhaust

EC-264
[QR (WITH EURO-OBD)]
DTC P0420 THREE WAY CATALYST FUNCTION

DTC P0420 THREE WAY CATALYST FUNCTIONPFP:20905
On Board Diagnosis LogicEBS010Q8
The ECM monitors the switching frequency ratio of heated oxygen
sensors 1 and 2.
A three way catalyst (manifold) with high oxygen storage capacity
will indicate a low switching frequency of heated oxygen sensor 2.
As oxygen storage capacity decreases, the heated oxygen sensor 2
switching frequency will increase.
When the frequency ratio of heated oxygen sensors 1 and 2
approaches a specified limit value, the three way catalyst (manifold)
malfunction is diagnosed.
DTC Confirmation ProcedureEBS010Q9
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.
WITH CONSULT-II
TESTING CONDITION:

Open engine hood before conducting the following procedure.

Do not hold engine speed for more than the specified minutes below.
1. Start Engine and warm it up to the normal operating temperature.
2. Turn ignition switch OFF and wait at least 10 seconds.
3. Start engine and keep the engine speed between 3,500 and 4,00 rpm for at least 1 minute under no load.
4. Let engine idle for 1 minute.
5. Select “DTC & SRT CONFIRMATION” then “SRT WORK SUP-
PORT” mode with CONSULT-II.
6. Start engine.
7. Rev engine up to 2,000 to 3,000 rpm and hold it for 3 consecu-
tive minutes then release the accelerator pedal completely.
If “INCMP” of “CATALYST” changed to “COMPLT”, go to step 10
8. Wait 5 seconds at idle.
SEF484YF
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0420
0420Catalyst system efficiency
below threshold

Three way catalyst (manifold) does not operate
properly.

Three way catalyst (manifold) does not have
enough oxygen storage capacity.

Three way catalyst (manifold)

Exhaust tube

Intake air leaks

Fuel injector

Fuel injector leaks

Spark plug

Improper ignition timing
PBIB0566E

EC-266
[QR (WITH EURO-OBD)]
DTC P0420 THREE WAY CATALYST FUNCTION

7. Make sure that the voltage switching frequency (high & low)
between ECM terminal 16 and ground is very less than that of
ECM terminal 35 and ground.
Switching frequency ratio = A/B
A: Heated oxygen sensor 2 voltage switching frequency
B: Heated oxygen sensor 1 voltage switching frequency
This ratio should be less than 0.75.
If the ratio is greater than above, it means three way catalyst
does not operate properly. Go to EC-266, "
Diagnostic Proce-
dure" .
NOTE:
If the voltage at terminal 35 does not switch periodically more than 5
times within 10 seconds at step 7, perform trouble diagnosis for DTC P0133 first. (See EC-186, "
DTC P0133
HO2S1" .)
Diagnostic ProcedureEBS010QB
1. CHECK EXHAUST SYSTEM
Visually check exhaust tubes and muffler for dent.
OK or NG
OK >> GO TO 2.
NG >> Repair or replace.
2. CHECK EXHAUST GAS LEAK
1. Start engine and run it at idle.
2. Listen for an exhaust gas leak before the three way catalyst (manifold).
OK or NG
OK >> GO TO 3.
NG >> Repair or replace.
3. CHECK INTAKE AIR LEAK
Listen for an intake air leak after the mass air flow sensor.
OK or NG
OK >> GO TO 4.
NG >> Repair or replace.
4. CHECK IGNITION TIMING
Check the following items. Refer to EC-79, "
Basic Inspection" .
MBIB0124E
SEC502D
Items Specifications
Target idle speedQR20DE with M/T models 650 ± 50 rpm (in Neutral position)
Except above 700 ± 50 rpm [in P or N (A/T), Neutral (M/T) position]
Ignition timing 15 ± 5° BTDC [in P or N (A/T), Neutral (M/T) position]

DTC P0444 EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE
EC-269
[QR (WITH EURO-OBD)]
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DTC P0444 EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE
PFP:14920
DescriptionEBS010QC
SYSTEM DESCRIPTION
*1: ECM determines the start signal status by the signals of engine speed and battery voltage.
*2: This signal is sent to the ECM through CAN communication line.
This system controls flow rate of fuel vapor from the EVAP canister. The opening of the vapor by-pass pas-
sage in the EVAP canister purge volume control solenoid valve changes to control the flow rate. The EVAP
canister purge volume control solenoid valve repeats ON/OFF operation according to the signal sent from the
ECM. The opening of the valve varies for optimum engine control. The optimum value stored in the ECM is
determined by considering various engine conditions. When the engine is operating, the flow rate of fuel vapor
from the EVAP canister is regulated as the air flow changes.
COMPONENT DESCRIPTION
The EVAP canister purge volume control solenoid valve uses a ON/
OFF duty to control the flow rate of fuel vapor from the EVAP canis-
ter. The EVAP canister purge volume control solenoid valve is
moved by ON/OFF pulses from the ECM. The longer the ON pulse,
the greater the amount of fuel vapor that will flow through the valve.
CONSULT-II Reference Value in Data Monitor ModeEBS010QD
Specification data are reference values.
On Board Diagnosis LogicEBS010QE
Sensor Input Signal to ECM ECM function Actuator
Crankshaft position sensor (POS)
Camshaft position sensor (PHASE)Engine speed*
1
EVAP canister
purge flow controlEVAP canister purge volume
control solenoid valve Mass air flow sensor Amount of intake air
Engine coolant temperature sensor Engine coolant temperature
Battery
Battery voltage*1
Throttle position sensor Throttle position
Accelerator pedal position sensor Closed throttle position
Heated oxygen sensor 1Density of oxygen in exhaust gas
(Mixture ratio feedback signal)
Wheel sensor*
2Vehicle speed
SEF337U
MONITOR ITEM CONDITION SPECIFICATION
PURG VOL C/V

Engine: After warming up

Shift lever: P or N (A/T), Neutral
(M/T)

Air conditioner switch: OFF

No loadIdle 0%
2,000 rpm 20 - 30%
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0444
0444EVAP canister purge volume
control solenoid valve circuit
openAn excessively low voltage signal is sent
to ECM through the valve

Harness or connectors
(The solenoid valve circuit is open or
shorted.)

EVAP canister purge volume control
solenoid valve

EC-322
[QR (WITH EURO-OBD)]
DTC P1143 HO2S1

DTC P1143 HO2S1PFP:22690
Component DescriptionEBS010S3
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 ModeEBS010S4
Specification data are reference values.
On Board Diagnosis LogicEBS010S5
To judge the malfunction, the output from the heated oxygen sensor
1 is monitored to determine whether the “rich” output is sufficiently
high and whether the “lean” output is sufficiently low. When both the
outputs are shifting to the lean side, the malfunction will be detected.
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)LEAN ←→ RICH
Changes more than 5 times dur-
ing 10 seconds.
SEF300U
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P1143
1143Heated oxygen sensor 1
lean shift monitoringThe maximum and minimum voltage from the
sensor are not reached to the specified voltages.

Heated oxygen sensor 1

Heated oxygen sensor 1 heater

Fuel pressure

Fuel injector

Intake air leaks

DTC P1143 HO2S1
EC-327
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Before installing new oxygen sensor, clean exhaust system threads using Oxygen Sensor Thread
Cleaner tool and approved anti-seize lubricant.
Without CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Set voltmeter probes between ECM terminal 35 (HO2S1 signal) and ground.
3. Check the following with engine speed held at 2,000 rpm con-
stant under no load.

The voltage fluctuates between 0 to 0.3V and 0.6 to 1.0V
more than 5 times within 10 seconds.

The maximum voltage is over 0.6V at least 1 time.

The minimum voltage is below 0.3V at least 1 time.

The voltage never exceeds 1.0V.
1 time: 0 - 0.3V → 0.6 - 1.0V → 0 - 0.3V
2 times: 0 - 0.3V → 0.6 - 1.0V → 0 - 0.3V → 0.6 - 1.0V
→ 0 - 0.3V
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 and approved anti-seize lubricant.
Removal and InstallationEBS010SA
HEATED OXYGEN SENSOR 1
Refer to EM-25, "EXHAUST MANIFOLD AND THREE WAY CATALYST" .
MBIB0018E

EC-328
[QR (WITH EURO-OBD)]
DTC P1144 HO2S1

DTC P1144 HO2S1PFP:22690
Component DescriptionEBS010SB
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 ModeEBS010SC
Specification data are reference values.
On Board Diagnosis LogicEBS010SD
To judge the malfunction, the output from the heated oxygen sensor
1 is monitored to determine whether the “rich” output is sufficiently
high and “lean” output is sufficiently low. When both the outputs are
shifting to the rich side, the malfunction will be detected.
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)LEAN ←→ RICH
Changes more than 5 times dur-
ing 10 seconds.
SEF299U
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P1144
1144Heated oxygen sensor 1
rich shift monitoringThe maximum and minimum voltages from the
sensor are beyond the specified voltages.

Heated oxygen sensor 1

Heated oxygen sensor 1 heater

Fuel pressure

Fuel injector

DTC P1144 HO2S1
EC-333
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6. Check the following.

“HO2S1 MNTR (B1)” in “DATA MONITOR” mode changes
from “RICH” to “LEAN” to “RICH” more than 5 times in 10 sec-
onds.
5 times (cycles) are counted as shown in the figure.

“HO2S1 (B1)” voltage goes above 0.6V at least once.

“HO2S1 (B1)” voltage goes below 0.3V at least once.

“HO2S1 (B1)” voltage never exceeds 1.0V.
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 and approved anti-seize lubricant.
Without CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Set voltmeter probes between ECM terminal 35 (HO2S1 signal) and ground.
3. Check the following with engine speed held at 2,000 rpm con-
stant under no load.

The voltage fluctuates between 0 to 0.3V and 0.6 to 1.0V
more than 5 times within 10 seconds.

The maximum voltage is over 0.6V at least 1 time.

The minimum voltage is below 0.3V at least 1 time.

The voltage never exceeds 1.0V.
1 time: 0 - 0.3V → 0.6 - 1.0V → 0 - 0.3V
2 times: 0 - 0.3V → 0.6 - 1.0V → 0 - 0.3V → 0.6 - 1.0V
→ 0 - 0.3V
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 and approved anti-seize lubricant.
Removal and InstallationEBS010SI
HEATED OXYGEN SENSOR 1
Refer to EM-25, "EXHAUST MANIFOLD AND THREE WAY CATALYST" .
SEF217YA
SEF648Y
MBIB0018E

EC-334
[QR (WITH EURO-OBD)]
DTC P1146 HO2S2

DTC P1146 HO2S2PFP:226A0
Component DescriptionEBS010SJ
The heated oxygen sensor 2, after three way catalyst (manifold),
monitors the oxygen level in the exhaust gas.
Even if switching characteristics of the heated oxygen sensor 1 are
shifted, the air-fuel ratio is controlled to stoichiometric, by the signal
from the heated oxygen sensor 2.
This sensor is made of ceramic zirconia. The zirconia generates volt-
age from approximately 1V in richer conditions to 0V in leaner condi-
tions.
Under normal conditions the heated oxygen sensor 2 is not used for
engine control operation.
CONSULT-II Reference Value in Data Monitor ModeEBS010SK
Specification data are reference values.
On Board Diagnosis LogicEBS010SL
The heated oxygen sensor 2 has a much longer switching time
between rich and lean than the heated oxygen sensor 1. The oxygen
storage capacity of the three way catalyst (manifold) causes the
longer switching time. To judge the malfunctions of heated oxygen
sensor 2, ECM monitors whether the minimum voltage of sensor is
sufficiently low during the various driving condition such as fuel-cut.
SEF327R
MONITOR ITEM CONDITION SPECIFICATION
HO2S2 (B1)

Engine: After warming up

Keeping the engine speed
between 3,500 and 4,000 rpm
for 1 minute and at idle for 1
minute under no load.Revving engine from idle to 3,000
rpm quickly.0 - 0.3V ←→ Approx. 0.6 - 1.0V
HO2S2 MNTR (B1)LEAN ←→ RICH
PBIB0554E
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P1146
1146Heated oxygen sensor 2
minimum voltage monitoringThe minimum voltage from the sensor is not
reached to the specified voltage.

Harness or connectors
(The sensor circuit is open or shorted.)

Heated oxygen sensor 2

Fuel pressure

Fuel injector