EC-178
< COMPONENT DIAGNOSIS >[HR16DE]
P0125 ECT SENSOR
P0125 ECT SENSOR
DescriptionINFOID:0000000006141201
The engine coolant temperature sensor is used to detect the engine
coolant temperature. The sensor modifies a voltage signal from the
ECM. The modified signal returns to the ECM as the engine coolant
temperature input. The sensor uses
a thermistor which is sensitive to
the change in temperature. The elec trical resistance of the ther-
mistor decreases as temperature increases.
*: These data are reference values and are measured between ECM terminal 38
(Engine coolant temperature sensor) and ground.
CAUTION:
Do not use ECM ground terminals when measuring input/output volt age. Doing so may result in damage to the ECM's transis-
tor. Use a ground other than ECM terminals, such as the ground.
DTC LogicINFOID:0000000005929865
DTC DETECTION LOGIC
NOTE:
• If DTC P0125 is displayed with P0116, first perfo rm the trouble diagnosis for DTC P0116. Refer to EC-
168, "DTC Logic".
• If DTC P0125 is displayed with P0117 or P0118, fi rst perform the trouble diagnosis for DTC P0117 or
P0118. Refer to EC-170, "
DTC Logic".
DTC CONFIRMATION PROCEDURE
1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
>> GO TO 2.
2.CHECK ENGINE COOLANT TEMPERATURE SENSOR FUNCTION
With CONSULT-III
1. Turn ignition switch ON.
SEF594K
Engine coolant temperature
[° C ( °F)] Voltage* (V)
Resistance (kΩ)
–10 (14) 4.47.0 - 11.4
20 (68) 3.52.37 - 2.63
50 (122) 2.20.68 - 1.00
90 (194) 0.90.236 - 0.260
SEF012P
DTC No. Trouble diagnosis name DTC detecting conditionPossible cause
P0125 Insufficient engine coolant
temperature for closed
loop fuel control • Voltage sent to ECM from the sensor is not
practical, even when some time has passed
after starting the engine.
• Engine coolant temperature is insufficient for
closed loop fuel control. • Harness or connectors
(High resistance in the circuit)
• Engine coolant temperature sensor
•Thermostat
Revision: May 2010 2011 Versa
P0441 EVAP CONTROL SYSTEMEC-283
< COMPONENT DIAGNOSIS > [HR16DE]
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TESTING CONDITION:
Always perform test at a temperature of 5
°C (41° F) or more.
>> GO TO 3.
3.PERFORM DTC CONFIRMATION PROCEDURE-I
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. Start engine and let it idle for at least 70 seconds.
4. Select “PURG FLOW P0441” of “EVAPORATIVE SYS TEM” in “DTC WORK SUPPORT” mode with CON-
SULT-III.
5. Touch “START”.
Is COMPLETED displayed on CONSULT-III screen?
YES >> GO TO 5.
NO >> GO TO 4.
4.PERFORM DTC CONFIRMATION PROCEDURE-II
When the following conditions are met, “TESTING” will be displayed on the CONSULT-III screen. Maintain the
conditions continuously until “TESTING” changes to “COMPLETED”. (It will take at least 35 seconds.)
CAUTION:
Always drive vehicle at a safe speed.
If “TESTING” is not changed for a long time, retry from step 2.
Is
“COMPLETED” displayed on CONSULT-III screen?
YES >> GO TO 5.
NO >> Perform DTC CONFIRMATION PROCEDURE again. GO TO 3.
5.PERFORM DTC CONFIRMATION PROCEDURE-II
Touch “SELF-DIAG RESULT”.
Which is displayed on CONSULT-III screen?
OK >> INSPECTION END
NG >> Go to EC-284, "
Diagnosis Procedure".
6.PERFORM COMPONENT FUNCTION CHECK
Perform component function check. Refer to EC-283, "
Component Function Check".
NOTE:
Use component function check to check the overall m onitoring function of the EVAP control system purge flow
monitoring. During this check, a 1s t trip DTC might not be confirmed.
Is the inspection result normal?
YES >> INSPECTION END
NO >> Go to EC-284, "
Diagnosis Procedure".
Component Function CheckINFOID:0000000005929953
1.PERFORM COMPONENT FUNCTION CHECK
Without CONSULT-III
1. Lift up drive wheels.
2. Start engine and warm it up to normal operating temperature.
3. Turn ignition switch OFF and wait at least 10 seconds.
4. Start engine and wait at least 70 seconds.
Selector lever Suitable position
VHCL SPEED SE 32 - 120 km/h (20 - 75 mph)
ENG SPEED 500 - 3,800 rpm
B/FUEL SCHDL 1.0 - 10.0 msec
COOLAN TEMP/S More than 0°C (32 °F)
Revision: May 2010 2011 Versa
EC-484
< ECU DIAGNOSIS >[HR16DE]
ECM
CATA-
LYST21H
Three way catalyst function
(Bank1) P0420 80H 01H O2 storage index
P0420 82H 01H
Switching time lag engine exhaust index
value
P2423 83H 0CH Difference in 3rd O2 sensor output volt-
age
P2423 84H 84H O2 storage index in HC trap catalyst
22H Three way catalyst function
(Bank2) P0430 80H 01H O2 storage index
P0430 82H 01H
Switching time lag engine exhaust index
value
P2424 83H 0CH Difference in 3rd O2 sensor output volt-
age
P2424 84H 84H O2 storage index in HC trap catalyst
EGR
SYSTEM 31H EGR function P0400 80H 96H
Low Flow Faults: EGR temp change
rate (short term)
P0400 81H 96H Low Flow Faults: EGR temp change
rate (long term)
P0400 82H 96H Low Flow Faults: Difference between
max EGR temp and EGR temp under
idling condition
P0400 83H 96H Low Flow Faults: Max EGR temp
P1402 84H 96H High Flow Faults: EGR temp increase
rate
VVT
SYSTEM 35H VVT Monitor (Bank1)
P0011 80H 9DH
VTC intake function diagnosis (VTC
alignment check diagnosis)
P0014 81H 9DH VTC exhaust function diagnosis (VTC
alignment check diagnosis)
P0011 82H 9DH VTC intake function diagnosis (VTC
drive failure diagnosis)
P0014 83H 9DH VTC exhaust function diagnosis (VTC
drive failure diagnosis)
36H VVT Monitor (Bank2) P0021 80H 9DH
VTC intake function diagnosis (VTC
alignment check diagnosis)
P0024 81H 9DH VTC exhaust function diagnosis (VTC
alignment check diagnosis)
P0021 82H 9DH VTC intake function diagnosis (VTC
drive failure diagnosis)
P0024 83H 9DH VTC exhaust function diagnosis (VTC
drive failure diagnosis)
Item
OBD-
MID Self-diagnostic test item
DTCTest value and Test
limit
(GST display) Description
TID Unit and
Scaling ID
Revision: May 2010 2011 Versa
FUEL PRESSUREEC-499
< ON-VEHICLE MAINTENANCE > [HR16DE]
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ON-VEHICLE MAINTENANCE
FUEL PRESSURE
InspectionINFOID:0000000005930166
FUEL PRESSURE RELEASE
With CONSULT-III
1. Turn ignition switch ON.
2. Perform “FUEL PRESSURE RELEASE” in
“WORK SUPPORT” mode with CONSULT-III.
3. Start engine.
4. After engine stalls, crank it two or three times to release all fuel pressure.
5. Turn ignition switch OFF.
Without CONSULT-III
1. Remove fuel pump fuse located in IPDM E/R.
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 (genuine
NISSAN 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.
PBIB2982E
Revision: May 2010 2011 Versa
EC-518
< SERVICE INFORMATION >[MR18DE]
ENGINE CONTROL SYSTEM
*1: This sensor is not used to control the engine system under normal conditions.
*2: This signal is sent to the ECM through CAN communication line.
*3: ECM determines the start signal status by the signals of engine speed and battery voltage.
SYSTEM DESCRIPTION
The amount of fuel injected from the fuel injector is
determined by the ECM. The ECM controls the length of
time the valve remains open (injection pulse duration). T he amount of fuel injected is a program value in the
ECM memory. The program value is preset by engine operating conditions. These conditions are determined
by input signals (for engine speed and intake air) from t he crankshaft position sensor (POS), camshaft position
sensor (PHASE) and the ma ss air flow sensor.
VARIOUS FUEL INJECTION I NCREASE/DECREASE COMPENSATION
In addition, the amount of fuel injected is compensated to improve engine performance under various operat-
ing conditions as listed below.
• When starting the engine
• During acceleration
• Hot-engine operation
• When selector lever is changed from N to D (A/T and CVT models)
• High-load, high-speed operation
• During high engine speed operation
MIXTURE RATIO FEEDBACK CONTROL (CLOSED LOOP CONTROL)
Sensor Input Signal to ECMECM functionActuator
Crankshaft position sensor (POS) Engine speed*
3
Piston position
Fuel injection
& mixture ratio
controlFuel injector
Camshaft position sensor (PHASE)
Mass air flow sensor
Amount of intake air
Engine coolant temperature sensor Engine coolant temperature
Air fuel ratio (A/F) sensor 1 Density of oxygen in exhaust gas
Throttle position sensor Throttle position
Accelerator pedal position sensor Accelerator pedal position
Park/neutral position (PNP) signal Gear position
Battery Battery voltage*
3
Knock sensorEngine knocking condition
EPS control unit Power steering operation*
2
Heated oxygen sensor 2*1Density of oxygen in exhaust gas
Air conditioner switch Air conditioner operation*
2
ABS actuator and electric unit (control unit)
Vehicle speed*2
Combination meter
PBIB3020E
Revision: May 2010 2011 Versa
ENGINE CONTROL SYSTEMEC-519
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The mixture ratio feedback system provides the best air/
fuel mixture ratio for drivability and emission control.
The three way catalyst (manifold) can then better r educe CO, HC and NOx emissions. This system uses air
fuel ratio (A/F) sensor 1 in the exhaust manifold to monitor whether the engine operation is rich or lean. The
ECM adjusts the injection pulse width according to the sensor voltage signal. For more information about air
fuel ratio (A/F) sensor 1, refer to EC-704
. This maintains the mixture ratio within the range of stoichiometric
(ideal air/fuel mixture).
This stage is referred to as the closed loop control condition.
Heated oxygen sensor 2 is located downstream of the th ree way catalyst (manifold). Even if the switching
characteristics of air fuel ratio (A/F) sensor 1 shift, the air/fuel ratio is controlled to stoichiometric by the signal
from heated oxygen sensor 2.
Open Loop Control
The open loop system condition refers to when the ECM detects any of the following conditions. Feedback
control stops in order to maintain stabilized fuel combustion.
• Deceleration and acceleration
• High-load, high-speed operation
• Malfunction of air fuel ratio (A/F) sensor 1 or its circuit
• Insufficient activation of air fuel ratio (A /F) sensor 1 at low engine coolant temperature
• High engine coolant temperature
• During warm-up
• After shifting from N to D (A/T and CVT models)
• When starting the engine
MIXTURE RATIO SELF-LEARNING CONTROL
The mixture ratio feedback control system monitors the mixture ratio signal tr ansmitted from air fuel ratio (A/F)
sensor 1. This feedback signal is then sent to the ECM. The ECM controls the basic mixture ratio as close to
the theoretical mixture ratio as possible. However, the bas ic mixture ratio is not necessarily controlled as orig-
inally designed. Both manufacturing differences (i.e., mass air flow sensor hot wire) and characteristic
changes during operation (i.e., fuel injector clogging) directly affect mixture ratio.
Accordingly, the difference between the basic and theoretical mixture ratios is monitored in this system. This is
then computed in terms of “injection pulse duration” to automatically compensate for the difference between
the two ratios.
“Fuel trim” refers to the feedback compensation value co mpared against the basic injection duration. Fuel trim
includes short term fuel trim and long term fuel trim.
“Short term fuel trim” is the short-term fuel compensati on used to maintain the mixture ratio at its theoretical
value. The signal from air fuel ratio (A/F) sensor 1 i ndicates whether the mixture ratio is RICH or LEAN com-
pared to the theoretical value. The signal then triggers a reduction in fuel volume if the mixture ratio is rich, and
an increase in fuel volume if it is lean.
“Long term fuel trim” is overall fuel compensation ca rried out long-term to compensate for continual deviation
of the short term fuel trim from the central value. Such deviation will occur due to individual engine differences,
wear over time and changes in the usage environment.
FUEL INJECTION TIMING
Two types of systems are used.
Sequential Multiport Fuel Injection System
Fuel is injected into each cylinder during each engine cycl e according to the firing order. This system is used
when the engine is running.
Simultaneous Multiport Fuel Injection System
Fuel is injected simultaneously into all four cylinders twice each engine cycle. In other words, pulse signals of
the same width are simultaneously transmitted from the ECM.
The four fuel injectors will then receive the signals two times for each engine cycle.
SEF337W
Revision: May 2010 2011 Versa
AUTOMATIC SPEED CONTROL DEVICE (ASCD)EC-523
< SERVICE INFORMATION > [MR18DE]
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AUTOMATIC SPEED CONTROL DEVICE (ASCD)
System DescriptionINFOID:0000000006341703
INPUT/OUTPUT SIGNAL CHART
*: This signal is sent to the ECM through CAN communication line.
BASIC ASCD SYSTEM
Refer to Owner's Manual for ASCD operating instructions.
Automatic Speed Control Device (ASCD) allows a driver to keep vehicle at predetermined constant speed
without depressing accelerator pedal. Driver can set
vehicle speed in advance between approximately 40 km/
h (25 MPH) and 144 km/h (89 MPH).
ECM controls throttle angle of electric thro ttle control actuator to regulate engine speed.
Operation status of ASCD is indicated by CRUISE i ndicator and SET indicator in combination meter. If any
malfunction occurs in ASCD system, it automatically deactivates control.
NOTE:
Always drive vehicle in safe manner according to traffic conditions and obey all traffic laws.
SET OPERATION
Press MAIN switch. (The CRUISE indicato r in combination meter illuminates.)
When vehicle speed reaches a desired speed between approximately 40 km/h (25 MPH) and 144 km/h (89
MPH), press SET/COAST switch. (Then SET indicator in combination meter illuminates.)
ACCELERATE OPERATION
If the RESUME/ACCELERATE switch is depressed during cruise control driving, increase the vehicle speed
until the switch is released or vehicle speed reaches maximum speed controlled by the system.
And then ASCD will keep the new set speed.
CANCEL OPERATION
When any of following conditions exis t, cruise operation will be canceled.
• CANCEL switch is pressed
• More than two switches at ASCD steering switch are pressed at the same time (Set speed will be cleared)
• Brake pedal is depressed
• Clutch pedal is depressed or gear position is changed to the neutral position (M/T models)
• Selector lever is changed to N, P, R position (A/T and CVT models)
• Vehicle speed decreased to 13 km/h (8 MPH) lower than the set speed
When the ECM detects any of the following conditions, the ECM will cancel the cruise operation and inform
the driver by blinking indicator lamp.
• Engine coolant temperature is slightly higher than the normal operating temperature, CRUISE lamp may blink slowly.
When the engine coolant temperature decreases to t he normal operating temperature, CRUISE lamp will
stop blinking and the cruise operation will be able to work by pressing SET/COAST switch or RESUME/
ACCELERATE switch.
• Malfunction for some self-diagnoses regarding ASCD control: SET lamp will blink quickly.
If MAIN switch is turned to OFF during ASCD is activated, all of ASCD operations will be canceled and vehicle
speed memory will be erased.
COAST OPERATION
Sensor Input signal to ECM ECM functionActuator
ASCD brake switch Brake pedal operation
ASCD vehicle speed controlElectric throttle control
actuator
Stop lamp switch
Brake pedal operation
ASCD clutch switch (M/T models) Clutch pedal operation
ASCD steering switch ASCD steering switch operation
Park/neutral position (PNP) signal Gear position
ABS actuator and electric unit (con-
trol unit) Vehicle speed*
Combination meter
TCM Powertrain revolution*
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