check engine light NISSAN LATIO 2011 Service Service Manual

ON BOARD DIAGNOSTIC (OBD) SYSTEMEC-541
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ON BOARD DIAGNOSTIC (OBD) SYSTEM
IntroductionINFOID:0000000006341717
The ECM has an on board diagnostic system, which detects malfunctions related to engine sensors or actua-
tors. The ECM also records various emission-related diagnostic information including:
*: Service $0A is not applied for regions where it is not mandated.
The above information can be checked using procedures listed in the table below.
×
: Applicable —: Not applicable
*: When DTC and 1st trip DTC simultaneously appear on the display, they cannot be clearly distinguished from each other.
The malfunction indicator lamp (MIL) on the instrument panel lights up when the same malfunction is detected
in two consecutive trips (Two trip detection logic), or when the ECM enters fail-safe mode.
(Refer to EC-590, "
Fail-Safe Chart".)
Two Trip Detection LogicINFOID:0000000006341718
When a malfunction is detected for the first time, 1st tr ip DTC and 1st trip Freeze Frame data are stored in the
ECM memory. The MIL will not light up at this stage. <1st trip>
If the same malfunction is detected again during the next drive, the DTC and Freeze Frame data are stored in
the ECM memory, and the MIL lights up. The MIL lights up at the same time when the DTC is stored. <2nd
trip> The “trip” in the “Two Trip Detection Logic” m eans a driving mode in which self-diagnosis is performed
during vehicle operation. Specific on board diagnostic item s will cause the ECM to light up or blink the MIL,
and store DTC and Freeze Frame data, even in the 1st trip, as shown below.
× : Applicable —: Not applicable
Emission-related diagnostic information Diagnostic service
Diagnostic Trouble Code (DTC) Service $03 of SAE J1979 /ISO 15031-5
Freeze Frame data Service $02 of SAE J1979/ISO 15031-5
System Readiness Test (SRT) code Service $01 of SAE J1 979/ISO 15031-5
1st Trip Diagnostic Trouble Code (1st Trip DTC) Service $07 of SAE J1979/ISO 15031-5
1st Trip Freeze Frame data —
Test values and Test limits Service $06 of SAE J1979/ISO 15031-5
Calibration ID Service $09 of SAE J1979/ISO 15031-5
Permanent Diagnostic Trouble Code (Permanent DTC) Service $0A* of SAE J1979/ISO 15031-5
DTC 1st trip DTCFreeze
Frame data 1st trip Freeze
Frame data SRT code SRT status Test value Permanent
DTC status
CONSULT-III ×× × × ×× —×
GST ×× × —××××
ECM ××*— — — ×——
Items MIL
DTC1st trip DTC
1st trip 2nd trip
1st trip
displaying 2nd trip
displaying 1st trip
displaying 2nd trip
display-
ing
Blinking Lighting
up Blinking
Lighting
up
Misfire (Possible three way catalyst
damage) — DTC: P0300 - P0304 is
being detected ×
———— — ×—
Misfire (Possible three way catalyst
damage) — DTC: P0300 - P0304 is
being detected ——
×—— ×——
One trip detection diagnoses
(Refer to EC-542, "
Emission-relat-
ed Diagnostic Information".) —
×—— ×———
Except above — — —×— ×× —
Revision: May 2010 2011 Versa

EC-546
< SERVICE INFORMATION >[MR18DE]
ON BOARD DIAGNOSTIC (OBD) SYSTEM
For malfunctions in which 1st trip DTCs are displa
yed, refer to "EMISSION-RELATED DIAGNOSTIC INFOR-
MATION ITEMS". These items are required by legal regulations 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/ ISO 15031-5. 1st trip DTC detection occurs without light-
ing 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 2, refer to EC-585, "
Trouble Diagnosis Introduction". Then per-
form DTC Confirmation Procedure or Overall Function Check 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/ISO 15031-6.
(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 malfunct ion. However, GST and the Diagnostic Test Mode II do not indi-
cate whether the malfunction is still occurring or h as occurred in the past and has returned to nor-
mal. CONSULT-III can identify ma lfunction 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 t he 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, engine 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 called freeze frame data and displayed on CONSULT-III or
GST. The 1st trip freeze frame data can only be disp layed on the CONSULT-III screen, not on the GST. For
details, see EC-612, "
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 memory along with the 1st trip DTC. There is no priority
for 1st trip freeze frame data and it is updated each time a different 1st trip DTC is detected. However, once
freeze frame data (2nd trip detection/MIL on) is stored in the ECM memory, 1st trip freeze frame data is no
longer stored. Remember, only one set of freeze frame data can be stored in the ECM. The ECM has the fol-
lowing priorities to update the data.
For example, the EGR malfunction (Priority: 2) was detected and the fr eeze frame data was stored in the 2nd
trip. After that when the misfire (Priority: 1) is detected in another trip, the freeze frame data will be updated
from the EGR malfunction to the misfire. The 1st trip freeze frame data is updated each time a different mal-
function is detected. There is no priority for 1st trip freeze frame data. However, once freeze frame data is
stored in the ECM memory, 1st trip freeze data is no longer stored (because only one freeze frame data or 1st
trip freeze frame data can be stored in the ECM). If fr eeze frame data is stored in the ECM memory and freeze
frame data with the same priority occurs later, t he first (original) freeze frame data remains unchanged in the
ECM memory.
Priority Items
1 Freeze frame data Misfire — DTC: P0300 - P0304
Fuel Injection System Function — DTC: P0171, P0172
2 Except the above items (Includes A/T or CVT related items)
3 1st trip freeze frame data
Revision: May 2010 2011 Versa

EC-566
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ON BOARD DIAGNOSTIC (OBD) SYSTEM
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-21
or see EC-1033.
2. When the engine is started, 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.
When there is an open circuit on MIL circuit, the ECM cannot warn the driver by MIL lighting up 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 diagnoses 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-542, "Emission-
related Diagnostic Information".
HOW TO SWITCH DIAGNOSTIC TEST MODE
NOTE:
•It is better to count the ti me accurately with a clock.
SEF217U
Diagnostic Test
Mode KEY and ENG.
Statu s 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
Revision: May 2010 2011 Versa

EC-576
< SERVICE INFORMATION >[MR18DE]
BASIC SERVICE PROCEDURE
OK or NG
OK >> GO TO 10.
NG >> GO TO 8.
8.DETECT MALFUNCTIONING PART
Check the following.
• Check crankshaft position sensor (POS) and circuit. Refer to EC-793
.
• Check camshaft position sensor (PHASE) and circuit.
Refer to EC-799
.
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 function. (ECM may be the cause of an incident, but this is a rare case.)
2. Perform initialization of NVIS (NATS) system and registration of all NVIS (NATS) ignition key IDs.
Refer to BL-247, "
ECM Re-communicating Function".
>> GO TO 4.
10.CHECK IGNITION TIMING
1. Run engine at idle.
2. Check ignition timing with a timing light. Refer to EC-578, "
Idle Speed and Ignition Timing Check".
- Timing indicator (1)
OK or NG
OK >> GO TO 19.
NG >> GO TO 11.
11 .PERFORM ACCELERATOR PEDAL RELEASED POSITION LEARNING
1. Stop engine.
2. Perform EC-580, "
Accelerator Pedal Released Position Learning".
>> GO TO 12.
12.PERFORM THROTTLE VALVE CL OSED POSITION LEARNING
Perform EC-580, "
Throttle Valve Closed Position Learning".
>> GO TO 13.
13.PERFORM IDLE AIR VOLUME LEARNING
Refer to EC-580, "
Idle Air Volume Learning".
Is Idle Air Volume Lear ning carried out successfully?
Ye s o r N o
M/T: 700 ± 50 rpm (in Neutral position)
A/T: 700 ± 50 rpm (in P or N position)
CVT: 700 ± 50 rpm (in P or N position)
M/T: 13 ± 5 ° BTDC (in Neutral position)
A/T: 13 ± 5 ° BTDC (in P or N position)
CVT: 13 ± 5 ° BTDC (in P or N position)
PBIB3263E
Revision: May 2010 2011 Versa

BASIC SERVICE PROCEDUREEC-577
< SERVICE INFORMATION > [MR18DE]
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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-578, "
Idle Speed and Ignition
Timing Check".
Without CONSULT-III
1. Start engine and warm it up to normal operating temperature.
2. Check idle speed. Refer to EC-578, "
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-578, "
Idle Speed and Ignition Timing Check".
- Timing indicator (1)
OK or NG
OK >> GO TO 19
NG >> GO TO 16.
16.CHECK TIMING CHAIN INSTALLATION
Check timing chain installation. Refer to EM-160, "
Removal and Installation".
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 crankshaft position sensor (POS) and circuit. Refer to EC-793
.
• Check camshaft position s ensor (PHASE) and circuit.
Refer to EC-799
.
OK or NG
OK >> GO TO 18.
NG >> 1. Repair or replace. 2. GO TO 4.
18.CHECK ECM FUNCTION M/T: 700
± 50 rpm (in Neutral position)
A/T: 700 ± 50 rpm (in P or N position)
CVT: 700 ± 50 rpm (in P or N position)
M/T: 700 ± 50 rpm (in Neutral position)
A/T: 700 ± 50 rpm (in P or N position)
CVT: 700 ± 50 rpm (in P or N position)
M/T: 13 ± 5 ° BTDC (in Neutral position)
A/T: 13 ± 5 ° BTDC (in P or N position)
CVT: 13 ± 5 ° BTDC (in P or N position)
PBIB3263E
Revision: May 2010 2011 Versa

BASIC SERVICE PROCEDUREEC-581
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• Electric load switch: OFF
[Air conditioner, headlamp, rear window defogger]
On vehicles equipped with daytime light systems, if the parking brake is applied before the engine is
started the headlamp will not be illuminated.
• Steering wheel: Neutral (Straight-ahead position)
• Vehicle speed: Stopped
• Transmission: Warmed-up
- Models with CONSULT-III (A/T and CVT models)
• Drive vehicle until “FLUID TEMP SE” in “DATA MONI TOR” mode of “A/T” or “CVT” system indicates less
than 0.9 V.
- Models without CONSULT-III (A/T and CVT models) and M/T models
• Drive vehicle for 10 minutes.
OPERATION PROCEDURE
With CONSULT-III
1. Perform EC-580, "Accelerator Pedal Released Position Learning".
2. Perform EC-580, "
Throttle Valve Closed Position Learning".
3. Start engine and warm it up to normal operating temperature.
4. Check that all items listed under the topic PREP ARATION (previously mentioned) are in good order.
5. Select “IDLE AIR VOL LEA RN” in “WORK SUPPORT” mode.
6. Touch “START” and wait 20 seconds.
7. Make sure that “CMPLT” is displayed on CONSULT-III screen. If “CMPLT” is not displayed, Idle Air Vol-
ume Learning will not be carried out successfully. In this case, find the cause of the incident by referring to
the DIAGNOSTIC PROCEDURE below.
8. Rev up the engine two or three times and make sure that idle speed and ignition timing are within the specifications.
Refer to EC-574, "
Basic Inspection".
Without CONSULT-III
NOTE:
•It is better to count the time accurately with a clock.
• It is impossible to switch the di agnostic mode when an accelerator pedal position sensor circuit has
a malfunction.
1. Perform EC-580, "
Accelerator Pedal Released Position Learning".
2. Perform EC-580, "
Throttle Valve Closed Position Learning".
3. Start engine and warm it up to normal operating temperature.
4. Check that all items listed under the topic PREP ARATION (previously mentioned) are in good order.
5. Turn ignition switch OFF and wait at least 10 seconds.
6. Confirm that accelerator pedal is fully releas ed, turn ignition switch ON and wait 3 seconds.
7. Repeat the following procedure quick ly five times within 5 seconds.
a. Fully depress the accelerator pedal.
b. Fully release the accelerator pedal.
8. Wait 7 seconds, fully depress the accelerator pedal and keep it for approx. 20 seconds until the MIL stops blinking and turned ON.
9. Fully release the accelerator pedal within 3 seconds after the MIL turned ON.
10. Start engine and let it idle.
Item Specification
Idle speed M/T: 700
± 50 rpm (in Neutral position)
A/T: 700 ± 50 rpm (in P or N position)
CVT: 700 ± 50 rpm (in P or N position)
Ignition timing M/T: 13
± 5 ° BTDC (in Neutral position)
A/T: 13 ± 5° BTDC (in P or N position)
CVT: 13 ± 5 ° BTDC (in P or N position)
Revision: May 2010 2011 Versa

BASIC SERVICE PROCEDUREEC-583
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1. Remove fuel pump fuse (1) located in IPDM E/R (2).
• : Vehicle front
2. Start engine.
3. After engine stalls, crank it two or three times to release all fuel pressure.
4. Turn ignition switch OFF.
5. Reinstall fuel pump fuse after servicing fuel system.
FUEL PRESSURE CHECK
CAUTION:
Before disconnecting fuel line, release fuel pressure from fuel line to eliminate danger.
NOTE:
• Prepare pans or saucers under the disconnected fuel line because the fuel may spill out. The fuel
pressure cannot be completely released because C11 models do not have fuel return system.
• The fuel hose connection method used when taking fuel pressure check must not be used for other
purposes.
• Be careful not to scratch or put debris around connection area when servicing, so that the quick
connector maintains seal abil ity with O-rings inside.
• Do not perform fuel pressure check with electrical systems operating (i.e. lights, rear defogger, A/C,
etc.) Fuel pressure gauge may indicate false readin gs due to varying engine load and changes in
manifold vacuum.
1. Release fuel pressure to zero. Refer to "FUEL PRESSURE RELEASE".
2. Prepare fuel hose for fuel pressure check B and fuel tube adapter (KV10118400) D, then connect fuel pressure gauge A.
• : To quick connector
• : To fuel tube (engine side)
• C: Clamp
• Use suitable fuel hose for fuel pressure check (genuineNISSAN fuel hose without quick connector).
• To avoid unnecessary force or tension to hose, use moder- ately long fuel hose for fuel pressure check.
• Do not use the fuel hose for checking fuel pressure with dam- age or cracks on it.
• Use Pressure Gauge to check fuel pressure.
3. Remove fuel hose. Refer to EM-154, "
Removal and Installation".
• Do not twist or kink fuel hose because it is plastic hose.
4. Connect fuel hose for fuel pressure check (1) to fuel tube (engine side) with clamp (2) as shown in the figure.
• No.2 spool (5)
• Wipe off oil or dirt from hose insertion part using cloth moist-ened with gasoline.
• Apply proper amount of gasoline between top of the fuel tube (3) and No.1 spool (4).
• Insert fuel hose for fuel pressure check until it touches the No.1 spool on fuel tube.
• Use NISSAN genuine hose clamp (part number: 16439 N4710
or 16439 40U00).
• When reconnecting fuel line, always use new clamps.
• Use a torque driver to tighten clamps.
• Install hose clamp to the positi on within 1 - 2 mm (0.04 - 0.08 in).
• Make sure that clamp screw does not contact adjacent parts.
PBIB2958E
Tightening torque: 1 - 1.5 N·m (0.1 - 0.15 kg-m, 9 - 13 in-lb)
PBIB2982E
PBIB2983E
Revision: May 2010 2011 Versa

TROUBLE DIAGNOSISEC-617
< SERVICE INFORMATION > [MR18DE]
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NOTE:
Any monitored item that does not match the vehicle being diagnosed is deleted from the display automatically.
ACTIVE TEST MODE
Test Item
HO2 S2 DIAG2 (B1)
[INCMP/CMPLT]
• Indicates DTC P0139 self-diagnosis (slow response) condi-
tion.
INCMP: Self-diagnosis is incomplete.
CMPLT: Self-diagnosis is complete.
A/F SEN1
DIAG1(B1)
[INCMP/CMPLT] • Indicates DTC P015A or P015B self-diagnosis condition.
INCMP: Self-diagnosis is incomplete.
CMPLT: Self-diagnosis is complete.
A/F SEN1
DIAG2(B1)
[INCMP/CMPLT] • Indicates DTC P014C or P014D self-diagnosis condition.
INCMP: Self-diagnosis is incomplete.
CMPLT: Self-diagnosis is complete.
A/F SEN1
DIAG3(B1)
[ABSNT/PRSNT] • Indicates DTC P014C, P014D, P015A or P015B self-diagno-
sis condition.
ABSNT: The vehicle condition is not within the diagnosis
range.
PRSNT: The vehicle condition is within the diagnosis range.
Monitored item [Unit]
Description Remarks
Test itemCondition JudgmentCheck 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
• Shift lever: P or N (A/T, CVT), Neutral (M/T)
• 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 “LOW”, “HI”
and “OFF” with CONSULT-III. Cooling fan moves and stops.
• Harness and connectors
• Cooling fan relay
• Cooling fan motor
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
FUEL PUMP RE-
LAY • Ignition switch: ON
(Engine stopped)
• Turn the fuel pump relay ON and
OFF using CONSULT-III and lis-
ten to operating sound. Fuel pump relay makes the operat-
ing sound.
• Harness and connectors
• Fuel pump relay
PURG VOL
CONT/V • Engine: After warming up, run en-
gine at 1,500 rpm.
• Change the EVAP canister purge volume control solenoid valve
opening percent using CON-
SULT-III. Engine speed changes according to
the opening percent.
• Harness and connectors
• EVAP canister purge volume con-
trol solenoid valve
FUEL/T TEMP
SEN • Change the fuel tank temperature using CONSULT-III.
Revision: May 2010
2011 Versa

DTC P0122, P0123 TP SENSOR
EC-691
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DTC P0122, P0123 TP SENSOR
Component DescriptionINFOID:0000000006341834
Electric throttle control actuator
consists of throttle control motor,
throttle position sensor, etc. 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 Val ue in Data Monitor ModeINFOID:0000000006341835
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 Diagnosis LogicINFOID:0000000006341836
These self-diagnoses have the on e trip detection logic.
NOTE:
If DTC P0122 or P0123 is displayed with DTC P0643, first perform the tro\
uble diagnosis for DTC P0643.
Refer to EC-898
.
FA I L - S A F E M O D E
When the malfunction is detected, ECM ent ers fail-safe mode and the MIL lights up.
DTC Confirmation ProcedureINFOID:0000000006341837
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:
Before performing the following procedure, confirm that battery voltage is more than 8 V at idle.
1. Start engine and let it idle for 1 second.
2. Check DTC.
3. If DTC is detected, go to EC-693, "
Diagnosis Procedure".
PBIB0145E
Monitor item Condition Specification
TP SEN 1-B1
TP SEN 2-B1* • Ignition switch: ON
(Engine stopped)
• Shift lever: D (A/T, CVT),
1st (M/T) Accelerator pedal: Fully released
More than 0.36 V
Accelerator pedal: Fully depressed Less than 4.75 V
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.)
• Electric throttle control actuator (TP 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.
Revision: May 2010 2011 Versa

EC-758
< SERVICE INFORMATION >[MR18DE]
DTC P0171 FUEL INJECTION SYSTEM FUNCTION
DTC P0171 FUEL INJECTION SYSTEM FUNCTION
On Board Diagn
osis LogicINFOID:0000000006341915
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 extremely large (The actual mixture ratio is too lean.),
the ECM judges the condition as the fuel injection sy stem malfunction and lights up the MIL (2 trip detection
logic).
DTC Confirmation ProcedureINFOID:0000000006341916
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-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. NOTE:
When depressing accelerator pedal three-fourths (3/4) or more, the control system does not start the
engine. Do not depress accelerator pedal too much.
b. If engine starts, go to EC-761, "
Diagnosis Procedure".
If engine does not start, check exhaus t and intake air leak visually.
6. Keep engine at idle for at least 5 minutes.
7. Check 1st trip DTC. The 1st trip DTC P0171 should be detected at this stage, if a malfunction exists. If so, go to EC-761,
"Diagnosis Procedure".
NOTE:
If 1st trip DTC is not detected during above proc edure, performing the following procedure is advised.
a. Turn ignition switch OFF and wait at least 10 seconds.
b. Start engine.
c. Maintain the following conditions for at least 10 consecutive minutes. Hold the accelerator pedal as steady as possible.
Sensor Input Signal to ECM ECM functionActuator
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 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
Revision: May 2010
2011 Versa