check engine light INFINITI FX35 2008 Owner's Manual

ON BOARD DIAGNOSTIC (OBD) SYSTEMEC-59
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*5: The trouble shooting for this DTC needs CONSULT-III.
*6: When the fail-safe operations for both self-diagnoses occur, the MIL illuminates.
*7: For models with ICC system.
*8: When the ECM is in the mode of displaying SRT status, MIL ma
y flash. For the details, refer to “How to Display SRT Status”.
DTC AND 1ST TRIP DTC
The 1st trip DTC (whose number is the same as the DTC number) is displayed for the latest self-diagnostic
result obtained. If the ECM memory was cleared previous ly, and the 1st trip DTC did not reoccur, the 1st trip
DTC will not be displayed.
If a malfunction is detected during the 1st trip, the 1st trip DTC is stored in the ECM memory. The MIL will not
light up (two trip detection logic). If the same malfunc tion is not detected in the 2nd trip (meeting the required
driving pattern), the 1st trip DTC is cleared from the ECM memory. If the same malfunction is detected in the
2nd trip, both the 1st trip DTC and DTC are stored in t he ECM memory and the MIL lights up. In other words,
the DTC is stored in the ECM memory and the MIL light s up when the same malfunction occurs in two consec-
utive trips. If a 1st trip DTC is stored and a non-diagnostic operation is performed between the 1st and 2nd
trips, only the 1st trip DTC will continue to be stored. Fo r malfunctions that blink or light up the MIL during the
1st trip, the DTC and 1st trip DTC are stored in the ECM memory.
Procedures for clearing the DTC and the 1st trip DT C from the ECM memory are described in “HOW TO
ERASE EMISSION-RELATED DIAGNOSTIC INFORMATION”.
For malfunctions in which 1st trip DTCs are displa yed, refer to “EMISSION-RELATED DIAGNOSTIC INFOR-
MATION ITEMS”. These items are required by legal r egulations to continuously monitor the system/compo-
nent. In addition, the items monitored non-cont inuously are also displayed on CONSULT-III.
1st trip DTC is specified in Service $07 of SAE J1979. 1st trip DTC detection occurs without lighting up the MIL
and therefore does not warn the driver of a malfunction. However, 1st trip DTC detection will not prevent the
vehicle from being tested, for example during Inspection/Maintenance (I/M) tests.
When a 1st trip DTC is detected, check, print out or write down and erase (1st trip) DTC and Freeze Frame
data as specified in Work Flow procedure Step II, refer to EC-89, "
Trouble Diagnosis Introduction". Then per-
form DTC Confirmation Procedure or Overall Function Che ck to try to duplicate the malfunction. If the mal-
function is duplicated, the item requires repair.
How to Read DTC and 1st Trip DTC
DTC and 1st trip DTC can be read by the following methods.
With CONSULT-III
With GST
CONSULT-III or GST (Generic Scan Tool ) Examples: P0340, P0850, P1148, etc.
These DTCs are prescribed by SAE J2012.
(CONSULT-III also displays the malfunctioning component or system.)
No Tools
The number of blinks of the MIL in the Diagnostic Test Mode II (Self-Diagnostic Results) indicates the DTC.
Example: 0340, 0850, 1148, etc.
These DTCs are controlled by NISSAN.
 1st trip DTC No. is the same as DTC No.
 Output of a DTC indicates a malfunc tion. However, GST or the Diagnostic Test Mode II do not indi-
cate whether the malfunction is stil l occurring or has occurred in the past and has returned to nor-
mal. CONSULT-III can identify malfunction status as shown below. Therefore, using CONSULT-III (if
available) is recommended.
DTC or 1st trip DTC of a malfunction is display ed in SELF-DIAGNOSTIC RESULTS mode of CONSULT-III.
Time data indicates how many times the vehicle was driven after the last detection of a DTC.
If the DTC is being detected currently, the time data will be [0].
If a 1st trip DTC is stored in the ECM, the time data will be [1t].
FREEZE FRAME DATA AND 1ST TRIP FREEZE FRAME DATA
The ECM records the driving conditions such as fuel system status, calculated load value, engine coolant tem-
perature, short term fuel trim, long term fuel trim, engi ne speed, vehicle speed, absolute throttle position, base
fuel schedule and intake air temperature at the moment a malfunction is detected.
Data which are stored in the ECM memory, along with the 1st trip DTC, are called 1st trip freeze frame data.
The data, stored together with the DTC data, are ca lled freeze frame data and displayed on CONSULT-III or
GST. The 1st trip freeze frame data can only be displa yed on the CONSULT-III screen, not on the GST. For
details, see EC-117, "
CONSULT-III Function (ENGINE)".
Only one set of freeze frame data (either 1st trip freez e frame data or freeze frame data) can be stored in the
ECM. 1st trip freeze frame data is stored in the ECM me mory along with the 1st trip DTC. There is no priority
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ON BOARD DIAGNOSTIC (OBD) SYSTEMEC-71
< SERVICE INFORMATION > [VQ35DE]
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1. If the ignition switch stays ON after repair work, be su
re to turn ignition switch OFF once. Wait at least 10
seconds and then turn it ON (engine stopped) again.
2. Perform AT-38, "
OBD-II Diagnostic Trouble Code (DTC)". (The DTC in TCM will be erased.)
3. Select Service $04 with GST (Generic Scan Tool).
No Tools
NOTE:
If the DTC is not for A/T related items (see EC-17
), skip step 2.
1. If the ignition switch stays ON after repair work, be sure to turn ignition switch OFF once.
Wait at least 10 seconds and then turn it ON (engine stopped) again.
2. Perform AT-38, "
OBD-II Diagnostic Trouble Code (DTC)". (The DTC in TCM will be erased.)
3. Change the diagnostic test mode from Mode II to Mode I by depressing the accelerator pedal. Refer to
EC-71, "
Malfunction Indicator Lamp (MIL)".
 If the battery is disconnected, the emission-relate d diagnostic information will be lost within 24
hours.
 The following data are cleared when the ECM memory is erased.
- Diagnostic trouble codes
- 1st trip diagnostic trouble codes
- Freeze frame data
- 1st trip freeze frame data
- System readiness test (SRT) codes
- Test values
Actual work procedures are explained using a DTC as an ex ample. Be careful so that not only the DTC, but all
of the data listed above, are cleared from the ECM memory during work procedures.
Malfunction Indicator Lamp (MIL)INFOID:0000000001325917
DESCRIPTION
The MIL is located on the instrument panel.
1. The MIL will light up when the ignition switch is turned ON with-
out the engine running. This is a bulb check.
If the MIL does not light up, refer to DI-34
or see EC-591.
2. When the engine is start ed, the MIL should go off.
If the MIL 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 three functions.
SEF217U
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EC-72
< SERVICE INFORMATION >[VQ35DE]
ON BOARD DIAGNOSTIC (OBD) SYSTEM
When there is an open circuit on MIL circuit, the ECM c
annot warn the driver by lighting up MIL when there is
malfunction on engine control system.
Therefore, when electrical controlled throttle and part of ECM related diagnoses are continuously detected as
NG for 5 trips, ECM warns the driver that engine cont rol system malfunctions and MIL circuit is open by means
of operating fail-safe function.
The fail-safe function also operates when above diagnos es except MIL circuit are detected and demands the
driver to repair the malfunction.
MIL Flashing Without DTC
When any SRT codes are not set, MIL may fl ash without DTC. For the details, refer to EC-55, "Emission-
Related Diagnostic Information".
HOW TO SWITCH DIAGNOSTIC TEST MODE
NOTE:
It is better to count the ti me accurately with a clock.
 It is impossible to switch the di agnostic mode when an accelerator pedal position sensor circuit has
a malfunction.
 Always ECM returns to Diagnostic Test Mode I after ignition switch is turned OFF.
How to Set Diagnostic Test Mode II (Self-Diagnostic Results)
1. Confirm that accelerator pedal is fully released, turn ignition switch ON and wait 3 seconds.
2. Repeat the following procedure quickly 5 times within 5 seconds.
a. Fully depress the accelerator pedal.
b. Fully release the accelerator pedal.
3. Wait 7 seconds, fully depress the accelerator pedal and keep it for approx. 10 seconds until the MIL starts
blinking.
NOTE:
Diagnostic Test
Mode KEY and ENG.
Status Function Explanation of Function
Mode I Ignition switch in ON position
Engine stopped BULB CHECK This function checks the MIL bulb for damage (blown, open
circuit, etc.).
If the MIL does not come on, check MIL circuit.
Engine running MALFUNCTION WARNING This is a usual driving condition. When a malfunction is de-
tected twice in two consecutive driving cycles (two trip de-
tection logic), the MIL will light up to inform the driver that a
malfunction has been detected.
The following malfunctions will light up or blink the MIL in
the 1st trip.
 Misfire (Possible three way catalyst damage)
 One trip detection diagnoses
Mode II Ignition switch in ON position
Engine stopped SELF-DIAGNOSTIC
RESULTS
This function allows DTCs an
d 1st trip DTCs to be read.
Engine operating condition in fail-safe mode Engine speed will not rise more than 2,500 rpm due to the fuel cut
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EC-82
< SERVICE INFORMATION >[VQ35DE]
BASIC SERVICE PROCEDURE
Check the following.
 Check camshaft position sensor (PHASE) and circuit.
Refer to EC-324
.
 Check crankshaft position sensor (POS) and circuit.
Refer to EC-319
.
OK or NG
OK >> GO TO 9.
NG >> 1. Repair or replace. 2. GO TO 4.
9.CHECK ECM FUNCTION
1. Substitute another known-good ECM to check ECM f unction. (ECM may be the cause of an incident, but
this is a rare case.)
2. Perform initialization of IVIS (NATS) system and registration of all IVIS (NATS) ignition key IDs.
Refer to BL-185
.
>> GO TO 4.
10.CHECK IGNITION TIMING
1. Run engine at idle.
2. Check ignition timing with a timing light. Refer to EC-84, "
Idle Speed and Ignition Timing Check".
OK or NG
OK >> GO TO 19.
NG >> GO TO 11.
11 .PERFORM ACCELERATOR PEDAL RELEASED POSITION LEARNING
1. Stop engine.
2. Perform EC-85, "
Accelerator Pedal Released Position Learning".
>> GO TO 12.
12.PERFORM THROTTLE VALVE CL OSED POSITION LEARNING
Perform EC-85, "
Throttle Valve Closed Position Learning".
>> GO TO 13.
13.PERFORM IDLE AIR VOLUME LEARNING
Refer to EC-85, "
Idle Air Volume Learning".
Is Idle Air Volume Lear ning carried out successfully?
Ye s o r N o
Yes >> GO TO 14.
No >> 1. Follow the instruction of Idle Air Volume Learning. 2. GO TO 4.
14.CHECK TARGET IDLE SPEED AGAIN
With CONSULT-III
1. Start engine and warm it up to normal operating temperature.
2. Read idle speed in “DATA MONITOR” mode with CONSULT-III. Refer to EC-84, "
Idle Speed and Ignition Timing Check".
15
± 5 ° BTDC (in P or N position)
PBIB1602E
650 ± 50 rpm (in P or N position)
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BASIC SERVICE PROCEDUREEC-83
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Without CONSULT-III
1. Start engine and warm it up to normal operating temperature.
2. Check idle speed. Refer to EC-84, "
Idle Speed and Ignition Timing Check".
OK or NG
OK >> GO TO 15.
NG >> GO TO 17.
15.CHECK IGNITION TIMING AGAIN
1. Run engine at idle.
2. Check ignition timing with a timing light. Refer to EC-84, "
Idle Speed and Ignition Timing Check".
OK or NG
OK >> GO TO 19.
NG >> GO TO 16.
16.CHECK TIMING CHAIN INSTALLATION
Check timing chain installation. Refer to EM-64
.
OK or NG
OK >> GO TO 17.
NG >> 1. Repair the timing chain installation. 2. GO TO 4.
17.DETECT MALFUNCTIONING PART
Check the following.
 Check camshaft position s ensor (PHASE) and circuit.
Refer to EC-324
.
 Check crankshaft position sensor (POS) and circuit.
Refer to EC-319
.
OK or NG
OK >> GO TO 18.
NG >> 1. Repair or replace. 2. GO TO 4.
18.CHECK ECM FUNCTION
1. Substitute another known-good ECM to check ECM f unction. (ECM may be the cause of an incident, but
this is a rare case.)
2. Perform initialization of IVIS (NATS) system and registration of all IVIS (NATS) ignition key IDs.
Refer to BL-185
.
>> GO TO 4.
19.INSPECTION END
Did you replace the ECM, referring this Basic Inspection procedure?
Ye s o r N o
Ye s > > 1 . P e r f o r m EC-84, "VIN Registration".
2. INSPECTION END
No >> INSPECTION END
650
± 50 rpm (in P or N position)
15 ± 5 ° BTDC (in P or N position)
PBIB1602E
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EC-84
< SERVICE INFORMATION >[VQ35DE]
BASIC SERVICE PROCEDURE
Idle Speed and Ignition Timing Check
INFOID:0000000001325920
IDLE SPEED
With CONSULT-III
Check idle speed in “DATA MONITOR” mode with CONSULT-III.
With GST
Check idle speed with Service $01 GST.
IGNITION TIMING
1. Attach timing light to loop wire as shown.
2. Check ignition timing.
Procedure After Replacing ECMINFOID:0000000001325921
When replacing ECM, the following procedure must be performed.
1. Perform initialization of IVIS (NATS) system and regist ration of all IVIS (NATS) ignition key IDs. Refer to
BL-187
.
2. Perform EC-84, "
VIN Registration".
3. Perform EC-85, "
Accelerator Pedal Released Position Learning".
4. Perform EC-85, "
Throttle Valve Closed Position Learning".
5. Perform EC-85, "
Idle Air Volume Learning".
VIN RegistrationINFOID:0000000001325922
DESCRIPTION
VIN Registration is an operation to registering VIN in ECM. It must be performed each time ECM is replaced.
NOTE:
Accurate VIN which is registered in ECM ma y be required for Inspection & Maintenance (I/M).
OPERATION PROCEDURE
With CONSULT-III
1. Check the VIN of the vehicle and note it. Refer to GI-45.
2. Turn ignition switch ON and engine stopped.
3. Select “VIN REGISTRATION ” in “WORK SUPPORT” mode.
PBIB1574E
PBIB1602E
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EC-124
< SERVICE INFORMATION >[VQ35DE]
TROUBLE DIAGNOSIS
NOTE:
Any monitored item that does not match the vehicle being diagnosed is deleted from the display automatically.
ACTIVE TEST MODE
Test Item
VHCL SPD CUTNON/
CUT  Indicates the vehicle cruise condition.
NON: Vehicle speed is maintained at the ASCD set
speed.
CUT: Vehicle speed increased to excessively high
compared with the ASCD set speed, and ASCD op-
eration is cut off.
LO SPEED CUT NON/
CUT  Indicates the vehicle cruise condition.
NON: Vehicle speed is maintained at the ASCD set
speed.
CUT: Vehicle speed decreased to excessively low
compared with the ASCD set speed, and ASCD op-
eration is cut off.
AT OD MONITOR ON/OFF  Indicates [ON/OFF] condition of A/T O/D according
to the input signal from the TCM.
AT OD CANCEL ON/OFF  Indicates [ON/OFF] condition of A/T O/D cancel
signal sent from the TCM.
DIST SW ON/OFF  Indicates [ON/OFF] condition from DISTANCE
switch signal.
CRUISE LAMP ON/OFF  Indicates [ON/OFF] condition of CRUISE lamp de-
termined by the ECM according to the input signals.
SET LAMP ON/OFF  Indicates [ON/OFF] condition of SET lamp deter-
mined by the ECM according to the input signals.
A/F ADJ-B1 —  Indicates the correction of factor stored in ECM. The factor is calculated from the difference be-
tween the target air-fuel ratio stored in ECM and the
air-fuel ratio calculated from A/F sensor 1 signal.
A/F ADJ-B2

w
Monitored item Unit Description Remarks
TEST ITEM CONDITION JUDGEMENT CHECK ITEM (REMEDY)
FUEL INJEC-
TION  Engine: Return to the original
trouble condition
 Change the amount of fuel injec- tion using CONSULT-III. If trouble symptom disappears, see
CHECK ITEM.
 Harness and connectors
 Fuel injector
 Air fuel ratio (A/F) sensor 1
IGNITION TIM-
ING  Engine: Return to the original
trouble condition
 Timing light: Set
 Retard the ignition timing using
CONSULT-III. If trouble symptom disappears, see
CHECK ITEM.
 Perform Idle Air Volume Learning.
POWER BAL-
ANCE  Engine: After warming up, idle the
engine.
 A/C switch: OFF
 Selector lever: P or N
 Cut off each fuel injector signal one at a time using CONSULT-III. Engine runs rough or dies.
 Harness and connectors
 Compression
 Fuel injector
 Power transistor
Spark plug
 Ignition coil
COOLING FAN* Ignition switch: ON
 Turn the cooling fan “HI”, “MID”,
“LOW” and “OFF” using CON-
SULT-III. Cooling fan moves and stops.
 Harness and connectors
 Cooling fan motor
 IPDM E/R
ENG COOLANT
TEMP  Engine: Return to the original
trouble condition
 Change the engine coolant tem-
perature using CONSULT-III. If trouble symptom disappears, see
CHECK ITEM.  Harness and connectors
 Engine coolant temperature sen-
sor
 Fuel injector
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EC-198
< SERVICE INFORMATION >[VQ35DE]
DTC P0122, P0123 TP SENSOR
DTC P0122, P0123 TP SENSOR
Component DescriptionINFOID:0000000001326020
Electric throttle control actuator
consists of throttle control motor,
throttle position (TP) sensor, et c. The throttle position sensor
responds to the throttle valve movement.
The throttle position sensor has two sensors. These sensors are a
kind of potentiometers which transform the throttle valve position into
output voltage, and emit the voltage signal to the ECM. In addition,
these sensors detect the opening and closing speed of the throttle
valve and feed the voltage signals to the ECM. The ECM judges the
current opening angle of the throttle valve from these signals and the
ECM controls the throttle control motor to make the throttle valve
opening angle properly in response to driving condition.
CONSULT-III Reference Value in Data Monitor ModeINFOID:0000000001326021
Specification data are reference values.
*: Throttle position sensor 2 signal is converted by ECM internally. Thus, it differs from ECM terminal voltage signal.
On Board Diagn osis LogicINFOID:0000000001326022
These self-diagnoses have the one trip detection logic.
FAIL-SAFE MODE
When the malfunction is detected, ECM enters fail-safe mode and the MIL lights up.
DTC Confirmation ProcedureINFOID:0000000001326023
NOTE:
If DTC Confirmation Procedure has been previously conduc ted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 8V at idle.
1. Start engine and let it idle for 1 second.
2. Check DTC.
3. If DTC is detected, go to EC-200, "
Diagnosis Procedure".
PBIB0145E
MONITOR ITEM CONDITION SPECIFICATION
TP SEN 1-B1
TP SEN 2-B1*  Ignition switch: ON
(Engine stopped)
 Selector lever: D Accelerator pedal:
Fully released More than 0.36V
Accelerator pedal: Fully depressed Less than 4.75V
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0122
0122 Throttle position sensor
2 circuit low input An excessively low voltage from the TP sensor
2 is sent to ECM.  Harness or connectors
(TP sensor 2 circuit is open or shorted.)
(APP sensor 2 circuit is shorted.)
 Electric throttle control actuator (TP sensor 2)
 Accelerator pedal position sensor (APP sensor 2)
P0123
0123
Throttle position sensor
2 circuit high input An excessively high voltage from the TP sensor
2 is sent to ECM.
Engine operation condition in fail-safe mode
The ECM controls the electric throttle control actuator in regulating the throttle opening in order for the idle position to be within +10
degrees.
The ECM regulates the opening speed of the throttle valve to be slower than the normal condition.
So, the acceleration will be poor.
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EC-274
< SERVICE INFORMATION >[VQ35DE]
DTC P0171, P0174 FUEL IN
JECTION SYSTEM FUNCTION
DTC P0171, P0174 FUEL INJECTION SYSTEM FUNCTION
On Board Diagnosis LogicINFOID:0000000001326101
With the Air-Fuel Mixture Ratio Self-Learning Control, the actual mixture ratio can be brought closely to the
theoretical mixture ratio based on the mixture ratio feedback signal from the air fuel ratio (A/F) sensor 1. The
ECM calculates the necessary compensation to corr ect the offset between the actual and the theoretical
ratios.
In case the amount of the compensation value is extrem ely large (the actual mixture ratio is too lean.), the
ECM judges the condition as the fuel injection system malfunction and lights up the MIL (2 trip detection logic).
DTC Confirmation ProcedureINFOID:0000000001609263
NOTE:
If DTC Confirmation Procedure has been previously conduc ted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
WITH CONSULT-III
1. Start engine and warm it up to normal operating temperature.
2. Turn ignition switch OFF and wait at least 10 seconds.
3. Turn ignition switch ON and select “SELF-LE ARNING CONT” in “WORK SUPPORT” mode with CON-
SULT-III.
4. Clear the self-learning control coefficient by touching “CLEAR”.
5. Start engine. If it is difficult to start engine, the fuel injection system has a malfunction.
Perform the following procedure is advised.
a. Crank engine while depressing accelerator pedal.
b. If engine starts, go to EC-279, "
Diagnosis Procedure".
If engine does not start, check exhaus t and intake air leak visually.
6. Keep engine at idle for at least 10 minutes.
7. Check 1st trip DTC.
8. If 1st trip DTC is detected, go to EC-279, "
Diagnosis Procedure".
If 1st trip DTC is not detected, per forming the following procedure is advised.
a. Turn ignition switch OFF and wait at least 10 seconds.
b. Start engine and drive the vehicle under the similar conditions to (1st trip) Freeze Frame Data for 10 min- utes. Refer to the table below.
Hold the accelerator pedal as steady as possible.
The similar conditions to (1st trip) Freeze Frame Da ta means the vehicle operation that the following con-
ditions should be satisfied at the same time.
Sensor Input signal to ECM ECM function Actuator
Air fuel ratio (A/F) sensor 1 Density of oxygen in exhaust gas
(Mixture ratio fe
edback signal) Fuel injection
control
Fuel injector
DTC No.
Trouble diagnosis
name DTC detecting condition Possible cause
P0171
0171
(Bank 1) Fuel injection system
too lean  Fuel injection system does not operate properly.
 The amount of mixture ratio compensation is too
large. (The mixture ratio is too lean.)  Intake air leaks
 Air fuel ratio (A/F) sensor 1
 Fuel injector
 Exhaust gas leaks
 Incorrect fuel pressure
 Lack of fuel
 Mass air flow sensor
 Incorrect PCV hose connection
P0174
0174
(Bank 2)
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EC-284
< SERVICE INFORMATION >[VQ35DE]
DTC P0172, P0175 FUEL IN
JECTION SYSTEM FUNCTION
DTC P0172, P0175 FUEL INJECTION SYSTEM FUNCTION
On Board Diagnosis LogicINFOID:0000000001326105
With the Air-Fuel Mixture Ratio Self-Learning Control, the actual mixture ratio can be brought closely to the
theoretical mixture ratio based on the mixture ratio feedback signal from the air fuel ratio (A/F) sensor 1. The
ECM calculates the necessary compensation to corr ect the offset between the actual and the theoretical
ratios.
In case the amount of the compensation value is extrem ely large (the actual mixture ratio is too rich.), the
ECM judges the condition as the fuel injection system malfunction and lights up the MIL (2 trip detection logic).
DTC Confirmation ProcedureINFOID:0000000001609264
NOTE:
If DTC Confirmation Procedure has been previously conduc ted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
WITH CONSULT-III
1. Start engine and warm it up to normal operating temperature.
2. Turn ignition switch OFF and wait at least 10 seconds.
3. Turn ignition switch ON and select “SELF-LE ARNING CONT” in “WORK SUPPORT” mode with CON-
SULT-III.
4. Clear the self-learning control coefficient by touching “CLEAR”.
5. Start engine. If it is difficult to start engine, the fuel injection system has a malfunction.
Perform the following procedure is advised.
a. Crank engine while depressing accelerator pedal.
b. If engine starts, go to . If engine does not start, remove ignition plugs and check for fouling, etc.
6. Keep engine at idle for at least 10 minutes.
7. Check 1st trip DTC.
8. If 1st trip DTC is detected, go to EC-289, "
Diagnosis Procedure".
If 1st trip DTC is not detected, per forming the following procedure is advised.
a. Turn ignition switch OFF and wait at least 10 seconds.
b. Start engine and drive the vehicle under the similar conditions to (1st trip) Freeze Frame Data for 10 min- utes. Refer to the table below.
Hold the accelerator pedal as steady as possible.
The similar conditions to (1st trip) Freeze Frame Da ta means the vehicle operation that the following con-
ditions should be satisfied at the same time.
Sensor Input signal to ECM ECM function Actuator
Air fuel ration (A/F) sensor 1 Density of oxygen in exhaust gas
(Mixture ratio feedback signal) Fuel injection
control
Fuel injector
DTC No.
Trouble diagnosis
name DTC detecting condition Possible cause
P0172
0172
(Bank 1) Fuel injection system
too rich  Fuel injection system does not operate properly.
 The amount of mixture ratio compensation is too
large. (The mixture ratio is too rich.)  Air fuel ratio (A/F) sensor 1
 Fuel injector
 Exhaust gas leaks
 Incorrect fuel pressure
 Mass air flow sensor
P0175
0175
(Bank 2)
Engine speed Engine speed in the freeze frame data
± 400 rpm
Vehicle speed Vehicle speed in the freeze frame data ± 10 km/h (6 MPH)
3AA93ABC3ACD3AC03ACA3AC03AC63AC53A913A773A893A873A873A8E3A773A983AC73AC93AC03AC3
3A893A873A873A8F3A773A9D3AAF3A8A3A8C3A863A9D3AAF3A8B3A8C