2004 INFINITI FX35 Engine

DTC P1140, P1145 IVT CONTROL POSITION SENSOR
EC-1099
[VK45DE]
C
D
E
F
G
H
I
J
K
L
MA
EC
Revision: 2004 November 2004 FX35/FX45
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.)
Diagnostic ProcedureABS00C9D
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.
TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
53 R/LIntake valve timing
control position sensor
(bank 2)[Engine is running]

Warm-up condition

Idle speed0 - 1.0V
[Engine is running]

Engine speed is 2,000 rpm0 - 1.0V
PBIB2046E
PBIB2195E

DTC P1143, P1163 HO2S1
EC-1103
[VK45DE]
C
D
E
F
G
H
I
J
K
L
MA
EC
Revision: 2004 November 2004 FX35/FX45
DTC P1143, P1163 HO2S1PFP:22690
Component DescriptionABS00C9G
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 1 to 0V.
CONSULT-II Reference Value in Data Monitor ModeABS00C9H
Specification data are reference values.
On Board Diagnosis LogicABS00C9I
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)
HO2S1 (B2)

Engine: After warming upMaintaining engine speed at 2,000
rpm0 - 0.3V ←→ Approx. 0.6 -
1.0V
HO2S1 MNTR (B1)
HO2S1 MNTR (B2)LEAN ←→ RICH
Changes more than 5 times
during 10 seconds.
SEF300U
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P1143
11 4 3
(Bank 1)
Heated oxygen sensor
1 lean shift monitoringThe maximum and minimum voltage from the
sensor are not reached to the specified volt-
ages.

Heated oxygen sensor 1

Heated oxygen sensor 1 heater

Fuel pressure

Fuel injector

Intake air leaks P1163
11 6 3
(Bank 2)

EC-1104
[VK45DE]
DTC P1143, P1163 HO2S1
Revision: 2004 November 2004 FX35/FX45
DTC Confirmation ProcedureABS00C9J
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 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 10 seconds.
3. Turn ignition switch ON and select “HO2S1 (B1) P1143” of “HO2S1” or “HO2S1 (B2) P1163” 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 EC-1105, "
Diagnostic
Procedure" .
PBIB0546E
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
PBIB0547E
SEC769C

DTC P1143, P1163 HO2S1
EC-1105
[VK45DE]
C
D
E
F
G
H
I
J
K
L
MA
EC
Revision: 2004 November 2004 FX35/FX45
Overall Function CheckABS00C9K
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] or 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 over 0.6V at least 1 time.
–The minimum voltage is over 0.1V at least 1 time.
4. If NG, go to EC-1105, "
Diagnostic Procedure" .
Diagnostic ProcedureABS00C9L
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.
PBIB1528E
PBIB2195E

EC-1106
[VK45DE]
DTC P1143, P1163 HO2S1
Revision: 2004 November 2004 FX35/FX45
2. RETIGHTEN HEATED OXYGEN SENSOR 1
Loosen and retighten corresponding heated oxygen sensor 1.
>> GO TO 3.
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 P0171 or P0174 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 P0171 or P0174 detected?
Is it difficult to start engine?
Ye s o r N o
Yes >> Perform trouble diagnosis for DTC P0171, P0174. Refer to EC-914 .
No >> GO TO 4.Tightening torque: 50 N·m (5.1 kg-m, 37 ft-lb)
PBIB1520E
SEF968Y
PBIB1502E

DTC P1143, P1163 HO2S1
EC-1107
[VK45DE]
C
D
E
F
G
H
I
J
K
L
MA
EC
Revision: 2004 November 2004 FX35/FX45
4. CHECK HEATED OXYGEN SENSOR 1 HEATER
Refer to EC-813, "
Component Inspection" .
OK or NG
OK >> GO TO 5.
NG >> Replace malfunctioning heated oxygen sensor 1.
5. CHECK HEATED OXYGEN SENSOR 1
Refer to EC-1107, "
Component Inspection" .
OK or NG
OK >> GO TO 6.
NG >> Replace malfunctioning heated oxygen sensor 1.
6. CHECK INTERMITTENT INCIDENT
Refer to EC-784, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
For circuit, refer to EC-865, "
Wiring Diagram" .
>>INSPECTION END
Component InspectionABS00C9M
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)/(B2)” and “HO2S1 MNTR (B1)/(B2)”.
4. Hold engine speed at 2,000 rpm under no load during the following steps.
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.
SEF646Y
SEF647Y

EC-1108
[VK45DE]
DTC P1143, P1163 HO2S1
Revision: 2004 November 2004 FX35/FX45
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.

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 InstallationABS00C9N
HEATED OXYGEN SENSOR 1
Refer to EM-178, "EXHAUST MANIFOLD AND THREE WAY CATALYST" .
SEF648Y
PBIB1528E

DTC P1144, P1164 HO2S1
EC-1109
[VK45DE]
C
D
E
F
G
H
I
J
K
L
MA
EC
Revision: 2004 November 2004 FX35/FX45
DTC P1144, P1164 HO2S1PFP:22690
Component DescriptionABS00C9O
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 1 to 0V.
CONSULT-II Reference Value in Data Monitor ModeABS00C9P
Specification data are reference values.
On Board Diagnosis LogicABS00C9Q
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)
HO2S1 (B2)

Engine: After warming upMaintaining engine speed at 2,000
rpm0 - 0.3V ←→ Approx. 0.6 -
1.0V
HO2S1 MNTR (B1)
HO2S1 MNTR (B2)LEAN ←→ RICH
Changes more than 5 times
during 10 seconds.
SEF299U
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P1144
11 4 4
(Bank 1)
Heated 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 P1164
11 6 4
(Bank 2)