Infiniti I30. Emission Control System (2003 year). Manual

DETECT MALFUNCTIONING PART

Check the following.

쐌

15A fuse

쐌

Harness for open and short between throttle control motor relay and fuse

䊳

Repair open circuit or short to ground or short to power in harness or connectors.

CHECK THROTTLE CONTROL MOTOR RELAY INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT

1. Disconnect ECM harness connector.
2. Check harness continuity between ECM terminal 102 and throttle control motor relay terminal 3.

Refer to Wiring Diagram.

Continuity should exist.

3. Also check harness for short to ground and short to power.

OK or NG

䊳

GO TO 5.

䊳

GO TO 4.

DETECT MALFUNCTIONING PART

Check the following.

쐌

Harness connector E15, F18

쐌

Harness for open and short between throttle control motor relay and ECM

䊳

Repair open circuit or short to ground or short to power in harness or connectors.

CHECK THROTTLE CONTROL MOTOR RELAY OUTPUT SIGNAL CIRCUIT FOR OPEN AND SHORT

1. Check harness continuity between ECM terminal 26 and throttle control motor relay terminal 1.

Refer to Wiring Diagram.

Continuity should exist.

2. Also check harness for short to ground and short to power.

OK or NG

䊳

GO TO 7.

䊳

GO TO 6.

DETECT MALFUNCTIONING PART

Check the following.

쐌

Harness connector E81, M15

쐌

Harness connectors M223, F53

쐌

Harness for open and short between throttle control motor relay and ECM

䊳

Repair open circuit or short to ground or short to power in harness or connectors.

CHECK THROTTLE CONTROL MOTOR RELAY

Refer to “Component Inspection”, EC-466.

OK or NG

䊳

GO TO 8.

䊳

Replace throttle control motor relay.

CHECK INTERMITTENT INCIDENT

Refer to “TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT”, EC-151.

䊳

INSPECTION END

IDX

DTC P1124, P1126 THROTTLE CONTROL MOTOR RELAY

Diagnostic Procedure (Cont’d)

EC-465

PBIB0098E

Component Inspection

NHEC1312

THROTTLE CONTROL MOTOR RELAY
1.

Apply 12V direct current between relay terminals 1 and 2.

Check continuity between relay terminals 3 and 5.

Conditions

Continuity

12V direct current supply between ter-
minals 1 and 2

Yes

No current supply

If NG, replace throttle control motor relay.

DTC P1124, P1126 THROTTLE CONTROL MOTOR RELAY

Component Inspection

EC-466

Component Description

NHEC1313

The throttle control motor is operated by the ECM and it opens and closes the throttle valve.
The current opening angle of the throttle valve is detected by the throttle position sensor and it provides feed-
back to the ECM to control the throttle control motor to make the throttle valve opening angle properly in
response to driving condition.

On Board Diagnosis Logic

NHEC1452

This self-diagnosis has the one trip detection logic.

DTC No.

Trouble diagnosis

name

DTC Detecting Condition

Possible Cause

P1128
1128

Throttle control motor
circuit short

ECM detects short both circuits between ECM and
throttle control motor.

쐌

Harness or connectors
(Throttle control motor circuit is
shorted.)

쐌

Electric throttle control actuator
(Throttle control motor)

FAIL-SAFE MODE

NHEC1452S01

When the malfunction is detected, ECM enters fail-safe mode and the MIL lights up.

Engine operating condition in fail-safe mode

ECM stops the electric throttle control actuator control, throttle valve is maintained at a fixed opening (approx. 5 degrees) by the
return spring.

DTC Confirmation Procedure

NHEC1453

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.

SEF058Y

With CONSULT-II

Turn ignition switch “ON” and wait at least 2 seconds.

Select “DATA MONITOR” mode with CONSULT-II.

Start engine and let it idle for 5 seconds.

If DTC is detected, go to “Diagnostic Procedure”, EC-469.

With GST

Follow the procedure “With CONSULT-II” above.

IDX

DTC P1128 THROTTLE CONTROL MOTOR

Component Description

EC-467

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.

TERMI-

NAL

NO.

WIRE

COLOR

ITEM

CONDITION

DATA (DC Voltage)

101

Throttle control motor
(Open)

[Ignition switch “ON”]

쐌

Engine stopped

쐌

Shift lever position is “D”

쐌

Accelerator pedal fully depressed

0 - 14V

★

SEC037D

103

Throttle control motor
(Close)

[Ignition switch “ON”]

쐌

Engine stopped

쐌

Shift lever position is “D”

쐌

Accelerator pedal released

0 - 14V

★

SEC038D

★

: Average voltage for pulse signal (Actual pulse signal can be confirmed by oscilloscope.)

Diagnostic Procedure

NHEC1317

RETIGHTEN GROUND SCREWS

1. Turn ignition switch “OFF”.
2. Loosen and retighten engine ground screws.

SEC047D

䊳

GO TO 2.

IDX

DTC P1128 THROTTLE CONTROL MOTOR

Wiring Diagram (Cont’d)

EC-469

CHECK THROTTLE CONTROL MOTOR OUTPUT SIGNAL CIRCUIT FOR OPEN OR SHORT

1. Turn ignition switch “OFF”.
2. Disconnect electric throttle control actuator harness connector.
3. Disconnect ECM harness connector.
4. Check harness continuity between the following terminals.

Refer to Wiring Diagram.

SEC054D

MTBL1169

5. Also check harness for short to ground and short to power.

OK or NG

䊳

GO TO 3.

䊳

Repair or replace.

CHECK THROTTLE CONTROL MOTOR

Refer to “Component Inspection”, EC-471.

OK or NG

䊳

GO TO 4.

䊳

GO TO 5.

CHECK INTERMITTENT INCIDENT

Refer to “TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT”, EC-151.

OK or NG

䊳

GO TO 5.

䊳

Repair or replace harness or connectors.

REPLACE ELECTRIC THROTTLE CONTROL ACTUATOR

1. Replace the electric throttle control actuator.
2. Perform “Throttle Valve Closed Position Learning”, EC-71.
3. Perform “Idle Air Volume Learning”, EC-71.

䊳

INSPECTION END

DTC P1128 THROTTLE CONTROL MOTOR

Diagnostic Procedure (Cont’d)

EC-470

PBIB0095E

Component Inspection

NHEC1318

THROTTLE CONTROL MOTOR
1.

Disconnect electric throttle control actuator harness connector.

Check resistance between terminals 3 and 6.

Resistance: Approximately 1 - 15

Ω

[at 25°C (77°F)]

If NG, replace electric throttle control actuator and go to next
step.

Perform “Throttle Valve Closed Position Learning”, EC-71.

Perform “Idle Air Volume Learning”, EC-71.

IDX

DTC P1128 THROTTLE CONTROL MOTOR

Component Inspection

EC-471

SEF463R

SEF288D

Component Description

NHEC1147

The heated oxygen sensor 1 is placed into the front tube. 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 approxi-
mately 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
Mode

NHEC1148

Specification data are reference values.

MONITOR ITEM

CONDITION

SPECIFICATION

HO2S1 (B1)
HO2S1 (B2)

쐌

Engine: After warming up

Maintaining engine speed at 2,000
rpm

0 - 0.3V

Approx. 0.6 - 1.0V

HO2S1 MNTR
(B1)
HO2S1 MNTR
(B2)

LEAN

RICH

Changes more than 5 times during
10 seconds.

SEF300U

On Board Diagnosis Logic

NHEC1150

To judge the malfunction, the output from the heated oxygen sen-
sor 1 is monitored to determine whether the “rich” output is suffi-
ciently high and whether the “lean” output is sufficiently low. When
both the outputs are shifting to the lean side, the malfunction will
be detected.

DTC P1143, P1163 HO2S1

Component Description

EC-472

DTC No.

Trouble diagnosis

name

DTC Detecting Condition

Possible Cause

P1143
1143
(Bank 1)
P1163
1163
(Bank 2)

Heated oxygen sen-
sor 1 lean shift moni-
toring

The maximum and minimum voltage from the
sensor are not reached to the specified voltages.

쐌

Heated oxygen sensor 1

쐌

Heated oxygen sensor 1 heater

쐌

Fuel pressure

쐌

Injectors

쐌

Intake air leaks

DTC Confirmation Procedure

NHEC1151

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:

쐌

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

쐌

Before performing following procedure, confirm that bat-
tery voltage is more than 11V at idle.

PBIB0546E

PBIB0547E

SEC769C

WITH CONSULT-II

NHEC1151S01

Start engine and warm it up to normal operating temperature.

Stop engine and wait at least 10 seconds.

Turn ignition switch “ON” and select “HO2S1 (B1)/(B2) P1143/
P1163” of “HO2S1” in “DTC WORK SUPPORT” mode with
CONSULT-II.

Touch “START”.

Start engine and let it idle for at least 3 minutes.

NOTE:
Never raise engine speed above 3,600 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
continuously until “TESTING” changes to “COMPLETED”. (It
will take approximately 50 seconds or more.)

ENG SPEED

1,200 - 2,600 rpm

Vehicle speed

Less than 100 km/h (62 MPH)

B/FUEL SCHDL

3 - 9 msec

Selector lever

Suitable position

If “TESTING” is not displayed after 5 minutes, retry from
step 2.

Make sure that “OK” is displayed after touching “SELF-DIAG
RESULTS”.

“NG”

displayed,

refer

“Diagnostic

Procedure”, EC-474.

IDX

DTC P1143, P1163 HO2S1

On Board Diagnosis Logic (Cont’d)

EC-473

SEC902C

Overall Function Check

NHEC1152

Use this procedure to check the overall function of the heated oxy-
gen sensor 1 circuit. During this check, a DTC might not be con-
firmed.

WITH GST

NHEC1152S01

Start engine and warm it up to normal operating temperature.

Set voltmeter probes between ECM terminal 91 (bank 1
HO2S1 signal) or 92 (bank 2 HO2S1 signal) and engine
ground.

Check one of the following with engine speed held at 2,000
rpm constant under no load.

쐌

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

쐌

The minimum voltage is over 0.1V at least one time.

If NG, go to “Diagnostic Procedure”, EC-474.

Diagnostic Procedure

NHEC1153

RETIGHTEN GROUND SCREWS

1. Turn ignition switch “OFF”.
2. Loosen and retighten engine ground screws.

SEC047D

䊳

GO TO 2.

RETIGHTEN HEATED OXYGEN SENSOR 1

Loosen and retighten corresponding heated oxygen sensor 1.

Tightening torque:

40 - 60 N·m (4.1 - 6.1 kg-m, 30 - 44 ft-lb)

䊳

GO TO 3.

DTC P1143, P1163 HO2S1

Overall Function Check

EC-474

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”.

SEF968Y

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?

Without CONSULT-II

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 connector.
5. Make sure DTC P0102 is displayed.
6. Erase the DTC memory. Refer to “HOW TO ERASE EMISSION-RELATED DIAGNOSTIC INFORMATION”, EC-89.
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?

Yes or No

Yes

䊳

Perform trouble diagnosis for DTC P0171, P0174. Refer to EC-267.

䊳

GO TO 4.

IDX

DTC P1143, P1163 HO2S1

Diagnostic Procedure (Cont’d)

EC-475

CHECK HEATED OXYGEN SENSOR 1 HEATER

1. Stop engine.
2. Disconnect HO2S1 harness connector.
3. Check resistance between HO2S1 terminals as follows.

SEF310X

CAUTION:

쐌

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.

쐌

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.

OK or NG

OK (With CONSULT-II)

䊳

GO TO 5.

OK (Without CONSULT-
II)

䊳

GO TO 6.

䊳

Replace malfunctioning heated oxygen sensor 1.

DTC P1143, P1163 HO2S1

Diagnostic Procedure (Cont’d)

EC-476

CHECK 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.

SEF967Y

6. Check the following.

쐌

“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 below.

SEF647Y

쐌

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

쐌

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

쐌

“HO2S1 (B1)/(B2)” voltage never exceeds 1.0V.

SEF648Y

CAUTION:

쐌

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.

쐌

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.

OK or NG

䊳

GO TO 7.

䊳

Replace malfunctioning heated oxygen sensor 1.

IDX

DTC P1143, P1163 HO2S1

Diagnostic Procedure (Cont’d)

EC-477

CHECK HEATED OXYGEN SENSOR 1

Without CONSULT-II

1. Start engine and warm it up to normal operating temperature.
2. Set voltmeter probes between ECM terminal 91 (HO2S1 bank 1 signal) or 92 (HO2S1 bank 2 signal) and engine

ground.

3. Check the following with engine speed held at 2,000 rpm constant under no load.

쐌

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

쐌

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

쐌

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

쐌

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

SEC085D

CAUTION:

쐌

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.

쐌

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.

OK or NG

䊳

GO TO 7.

䊳

Replace malfunctioning heated oxygen sensor 1.

CHECK INTERMITTENT INCIDENT

Refer to “TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT”, EC-151.
For circuit, refer to “Wiring Diagram”, EC-232.

䊳

INSPECTION END

DTC P1143, P1163 HO2S1

Diagnostic Procedure (Cont’d)

EC-478

SEF463R

SEF288D

Component Description

NHEC1154

CONSULT-II Reference Value in Data Monitor
Mode

NHEC1155

Specification data are reference values.

MONITOR ITEM

CONDITION

SPECIFICATION

HO2S1 (B1)
HO2S1 (B2)

쐌

Engine: After warming up

Maintaining engine speed at 2,000
rpm

0 - 0.3V

Approx. 0.6 - 1.0V

HO2S1 MNTR
(B1)
HO2S1 MNTR
(B2)

LEAN

RICH

Changes more than 5 times during
10 seconds.

SEF299U

On Board Diagnosis Logic

NHEC1157

To judge the malfunction, the output from the heated oxygen sen-
sor 1 is monitored to determine whether the “rich” output is suffi-
ciently high and “lean” output is sufficiently low. When both the
outputs are shifting to the rich side, the malfunction will be
detected.

IDX

DTC P1144, P1164 HO2S1

Component Description

EC-479

DTC No.

Trouble diagnosis

name

DTC Detecting Condition

Possible Cause

P1144
1144
(Bank 1)
P1164
1164
(Bank 2)

Heated oxygen sen-
sor 1 rich shift moni-
toring

The maximum and minimum voltages from the
sensor are beyond the specified voltages.

쐌

Heated oxygen sensor 1

쐌

Fuel pressure

쐌

Injectors

쐌

Heated oxygen sensor 1 heater

DTC Confirmation Procedure

NHEC1158

CAUTION:

쐌

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

쐌

Before performing the following procedure, confirm that
battery voltage is more than 11V at idle.

PBIB0548E

PBIB0549E

SEC772C

WITH CONSULT-II

NHEC1158S01

Start engine and warm it up to normal operating temperature.

Stop engine and wait at least 5 seconds.

Turn ignition switch “ON” and select “HO2S1 (B1)/(B2) P1144/
P1164” of “HO2S1” in “DTC WORK SUPPORT” mode with
CONSULT-II.

Touch “START”.

Start engine and let it idle for at least 3 minutes.

NOTE:
Never raise engine speed above 3,600 rpm after this step. If
the engine speed limit is exceeded, return to step 5.
6)

ENG SPEED

1,200 - 2,600 rpm

Vehicle speed

Less than 100 km/h (62 MPH)

B/FUEL SCHDL

3 - 9 msec

Selector lever

Suitable position

If “TESTING” is not displayed after 5 minutes, retry from
step 2.

Make sure that “OK” is displayed after touching “SELF-DIAG
RESULTS”.

“NG”

displayed,

refer

“Diagnostic

Procedure”, EC-481.

DTC P1144, P1164 HO2S1

On Board Diagnosis Logic (Cont’d)

EC-480

Infiniti I30. Emission Control System (2003 year). Manual - part 30