2004 INFINITI FX35 Engine

EC-1110
[VK45DE]
DTC P1144, P1164 HO2S1
Revision: 2004 November 2004 FX35/FX45
DTC Confirmation ProcedureABS00C9R
CAUTION:
Always drive vehicle at a safe speed.
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:

Always perform at a temperature above −10°C (14°F).

Before performing the following procedure, confirm that battery voltage is more than 11V at idle.
WITH CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Stop engine and wait at least 5 seconds.
3. Turn ignition switch ON and select “HO2S1 (B1) P1144” or “HO2S1 (B2) P1164” of “HO2S1” in “DTC
WORK SUPPORT” mode with CONSULT-II.
4. Touch “START”.
5. Start engine and let it idle for at least 3 minutes.
NOTE:
Do not raise engine speed above 3,000 rpm after this step. If
the engine speed limit is exceeded, return to step 5.
6. When the following conditions are met, “TESTING” will be dis-
played on the CONSULT-II screen. Maintain the conditions con-
tinuously until “TESTING” changes to “COMPLETED”. (It will
take approximately 40 seconds or more.)
If “TESTING” is not displayed after 5 minutes, retry from
step 2.
7. Make sure that “OK” is displayed after touching “SELF-DIAG
RESULTS”. If “NG” is displayed, refer to E C - 1111 , "
Diagnostic
Procedure" .
PBIB0548E
ENG SPEED 1,200 - 2,500 rpm
VHCL SPEED SE Less than 100 km/h (62 MPH)
B/FUEL SCHDL 1.6 - 12.0 msec
Selector lever Suitable position
PBIB0549E
SEC772C

DTC P1144, P1164 HO2S1
EC-1111
[VK45DE]
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Revision: 2004 November 2004 FX35/FX45
Overall Function CheckABS00C9S
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 GST
1. Start engine and warm it up to normal operating temperature.
2. Set voltmeter probes between ECM terminal 16 [HO2S1(B1) signal] 35 [HO2S1(B2) signal] and ground.
3. Check one of the following with engine speed held at 2,000 rpm
constant under no load.
–The maximum voltage is below 0.8V at least 1 time.
–The minimum voltage is below 0.35V at least 1 time.
4. If NG, go to EC-1111, "
Diagnostic Procedure" .
Diagnostic ProcedureABS00C9T
1. CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten three ground screws on the body.
Refer to EC-791, "
Ground Inspection" .
OK or NG
OK >> GO TO 2.
NG >> Repair or replace ground connections.
2. RETIGHTEN HEATED OXYGEN SENSOR 1
Loosen and retighten heated oxygen sensor 1.
>> GO TO 3.
PBIB1528E
PBIB2195E
Tightening torque: 50 N·m (5.1 kg-m, 37 ft-lb)
PBIB1520E

EC-1112
[VK45DE]
DTC P1144, P1164 HO2S1
Revision: 2004 November 2004 FX35/FX45
3. CLEAR THE SELF-LEARNING DATA
With CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Select “SELF-LEARNING CONT” in “WORK SUPPORT” mode with CONSULT-II.
3. Clear the self-learning control coefficient by touching “CLEAR”.
4. Run engine for at least 10 minutes at idle speed.
Is the 1st trip DTC P0172 or P0175 detected?
Is it difficult to start engine?
With GST
1. Start engine and warm it up to normal operating temperature.
2. Turn ignition switch OFF.
3. Disconnect mass air flow sensor harness connector, and restart
and run engine for at least 5 seconds at idle speed.
4. Stop engine and reconnect mass air flow sensor harness con-
nector.
5. Make sure DTC P0102 is displayed.
6. Erase the DTC memory. Refer to EC-715, "
HOW TO ERASE
EMISSION-RELATED DIAGNOSTIC INFORMATION" .
7. Make sure DTC P0000 is displayed.
8. Run engine for at least 10 minutes at idle speed.
Is the 1st trip DTC P0172 or P0175 detected?
Is it difficult to start engine?
Ye s o r N o
Yes >> Perform trouble diagnosis for DTC P0172, P0175. Refer to EC-923 .
No >> GO TO 4.
SEF968Y
PBIB1502E

DTC P1144, P1164 HO2S1
EC-1113
[VK45DE]
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Revision: 2004 November 2004 FX35/FX45
4. CHECK HO2S1 CONNECTOR FOR WATER
1. Turn ignition switch OFF.
2. Disconnect heated oxygen sensor 1 harness connector.
3. Check connectors for water.
OK or NG
OK >> GO TO 5.
NG >> Repair or replace harness or connectors.
5. CHECK HEATED OXYGEN SENSOR 1 HEATER
Refer to EC-813, "
Component Inspection" .
OK or NG
OK >> GO TO 6.
NG >> Replace malfunctioning heated oxygen sensor 1.
6. CHECK HEATED OXYGEN SENSOR 1
Refer to E C - 111 3 , "
Component Inspection" .
OK or NG
OK >> GO TO 7.
NG >> Replace malfunctioning heated oxygen sensor 1.
7. CHECK INTERMITTENT INCIDENT
Refer to EC-784, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
For circuit, refer to EC-865, "
Wiring Diagram" .
>>INSPECTION END
Component InspectionABS00C9U
HEATED OXYGEN SENSOR 1
With CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Select “MANU TRIG” and adjust “TRIGGER POINT” to 100% in “DATA MONITOR” mode with CONSULT-
II.
3. Select “HO2S1 (B1)” and “HO2S1 MNTR (B1)”.
4. Hold engine speed at 2,000 rpm under no load during the following steps.Water should not exist.
PBIB1521E

EC-1114
[VK45DE]
DTC P1144, P1164 HO2S1
Revision: 2004 November 2004 FX35/FX45
5. Touch “RECORD” on CONSULT-II screen.
6. Check the following.

“HO2S1 MNTR (B1)/(B2)” in “DATA MONITOR” mode
changes from “RICH” to “LEAN” to “RICH” more than 5 times
in 10 seconds.
5 times (cycles) are counted as shown at right.

“HO2S1 (B1)/(B2)” voltage goes above 0.6V at least once.

“HO2S1 (B1)/(B2)” voltage goes below 0.3V at least once.

“HO2S1 (B1)/(B2)” 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 J-43897-18 or J-43897-12 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 16 [HO2S1 (B1) signal] or 35 [HO2S1 (B2) 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.
SEF646Y
SEF647Y
SEF648Y
PBIB1528E

EC-1116
[VK45DE]
DTC P1146, P1166 HO2S2
Revision: 2004 November 2004 FX35/FX45
DTC P1146, P1166 HO2S2PFP:226A0
Component DescriptionABS00C9W
The heated oxygen sensor 2, after three way catalyst (manifold),
monitors the oxygen level in the exhaust gas on each bank.
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 ModeABS00C9X
Specification data are reference values.
On Board Diagnosis LogicABS00C9Y
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)
HO2S2 (B2)

Warm-up condition

After keeping engine speed
between 3,500 and 4,000 rpm for
1 minute and at idle for 1 minute
under no loadRevving engine from idle to 3,000 rpm
quickly0 - 0.3V ←→ Approx. 0.6 -
1.0V
HO2S2 MNTR (B1)
HO2S2 MNTR (B2)LEAN ←→ RICH
SEF972Z
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P1146
1146
(Bank 1)Heated 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 P1166
1166
(Bank 2)

DTC P1146, P1166 HO2S2
EC-1117
[VK45DE]
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Revision: 2004 November 2004 FX35/FX45
DTC Confirmation ProcedureABS00C9Z
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:
For better results, perform “DTC WORK SUPPORT” at a temperature of 0 to 30 °C (32 to 86 °F).
1. Turn ignition switch ON and select “DATA MONITOR” mode with
CONSULT-II.
2. Start engine and warm it up to the normal operating tempera-
ture.
3. Turn ignition switch OFF and wait at least 10 seconds.
4. Start engine and keep the engine speed between 3,500 and
4,000 rpm for at least 1 minute under no load.
5. Let engine idle for 1 minute.
6. Make sure that “COOLAN TEMP/S” indicates more than 70°C
(158°F).
If not, warm up engine and go to next step when “COOLAN
TEMP/S” indication reaches to 70°C (158°F).
7. Open engine hood.
8. Select “HO2S2 (B1) P1146” or “HO2S2 (B2) P1166” of “HO2S2” in “DTC WORK SUPPORT” mode with
CONSULT-II.
9. Start engine and following the instruction of CONSULT-II.
10. Make sure that “OK” is displayed after touching “SELF-DIAG RESULTS”.
If “NG” is displayed, refer to EC-1122, "
Diagnostic Procedure" .
If “CAN NOT BE DIAGNOSED” is displayed, perform the following.
a. Turn ignition switch OFF and leave the vehicle in a cool place (soak the vehicle).
b. Return to step 1.
Overall Function CheckABS00CA0
Use this procedure to check the overall function of the heated oxygen sensor 2 circuit. During this check, a 1st
trip DTC might not be confirmed.
WITH GST
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 4,000 rpm for at least 1 minute under no load.
4. Let engine idle for 1 minute.
5. Set voltmeter probes between ECM terminal 55 [HO2S2 (B1) signal] or 74 [HO2S2 (B2) signal] and
ground.
SEF174Y
PBIB0818E

EC-1120
[VK45DE]
DTC P1146, P1166 HO2S2
Revision: 2004 November 2004 FX35/FX45
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.
TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
55 W/RHeated oxygen sensor 2
(bank 1)[Engine is running]

Warm-up condition

Revving engine from idle to 3,000 rpm
quickly after the following conditions are met
–After keeping the engine speed between
3,500 and 4,000 rpm for 1 minute and at idle
for 1 minute under no load0 - Approximately 1.0V
78 B/RSensor ground
(Heated oxygen sensor)[Engine is running]

Warm-up condition

Idle speedApproximately 0V