ECM
EC-467
< ECU DIAGNOSIS > [HR16DE]
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DTC Inspection Priority ChartINFOID:0000000005398638
If some DTCs are displayed at the same time, perform inspections one by one based on the following priority
chart.
P2119 Electric thro
ttle control ac-
tuator (When electric throttle control actuator does not function properly due to the return spring
malfunction:)
ECM controls the electric throttle actuator by regulating the throttle opening around the
idle position. The engine speed will not rise more than 2,000 rpm.
(When throttle valve opening angle in fail-safe mode is not in specified range:)
ECM controls the electric throttle control actuator by regulating the throttle opening to 20
degrees or less.
(When ECM detects the throttle valve is stuck open:)
While the vehicle is driving, it slows down gradually by fuel cut. After the vehicle stops, the
engine stalls.
The engine can restart in N or P (A/T), Neutral (M/T) position, and engine speed will not
exceed 1,000 rpm or more.
P2122
P2123
P2127
P2128
P2138 Accelerator pedal position
sensor
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.
DTC No. Detected items
Engine operating condition in fail-safe mode
PriorityDetected items (DTC)
1 • U0101 U0140 U1001 CAN communication line • P0101 P0102 P0103 Mass air flow sensor
• P0112 P0113 P0127 Intake air temperature sensor
• P0116 P0117 P0118 P0125 Engine coolant temperature sensor
• P0122 P0123 P0222 P0223 P1225 P1226 P2135 Throttle position sensor
• P0128 Thermostat function
• P0181 P0182 P0183 Fuel tank temperature sensor
• P0327 P0328 Knock sensor
• P0335 Crankshaft position sensor (POS)
• P0340 Camshaft position sensor (PHASE)
• P0460 P0461 P0462 P0463 Fuel level sensor
• P0500 Vehicle speed sensor
• P0605 P0607 ECM
• P0643 Sensor power supply
• P0705 Transmission range switch
• P0850 Park/neutral position (PNP) switch
• P1610 - P1615 NATS
• P2122 P2123 P2127 P2128 P2138 Accelerator pedal position sensor
Revision: January 20102010 Versa
ECM
EC-473
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• Sea level
• Flat road
• Ambient air temperature: 20 - 30
°C (68 - 86 °F)
• Diagnosis is performed as quickly as possible under normal conditions. Under different conditions [For example: ambient air temperature other than 20 - 30 °C (68 - 86° F)], diagno-
sis may also be performed.
Pattern 1:
• The engine is started at the engine coolant temperature of −10 to 35 °C (14 to 95 °F)
(where the voltage between the ECM te rminal 38 and ground is 3.0 - 4.3 V).
• The engine must be operated at idle speed until the engine coolant temperature is greater than 70 °C
(158° F) (where the voltage between the ECM te rminal 38 and ground is lower than 1.4 V).
• The engine is started at the fuel tank temperature of warmer than 0 °C (32° F) (where the voltage
between the ECM terminal 43 and ground is less than 4.1 V).
Pattern 2:
• When steady-state driving is performed again even afte r it is interrupted, each diagnosis can be conducted.
In this case, the time required for diagnosis may be extended.
Pattern 3:
• Operate vehicle following the driving pattern shown in the figure.
• Release the accelerator pedal during decelerating vehicle speed from 90 km/h (56 MPH) to 0 km/h (0 MPH).
Pattern 4:
• The accelerator pedal must be held very steady during steady- state driving.
• If the accelerator pedal is moved, the test must be conducted again.
*1: Depress the accelerator pedal until vehicle speed is 90 km/h (56
MPH), then release the accelerator pedal and keep it released for
more than 10 seconds. Depress the accelerator pedal until vehicle
speed is 90 km/h (56 MPH) again.
*2: Checking the vehicle speed with GST is advised.
Suggested Transmission Gear Position for A/T Models
Set the selector lever in the D position.
Suggested Upshift Speeds for M/T Models
Shown below are suggested vehicle speeds for shifting into a higher gear. These suggestions relate to fuel
economy and vehicle performance. Actual upshift speeds will vary according to road conditions, the weather
and individual driving habits.
How to Erase Permanent DTCINFOID:0000000005647832
When a DTC is stored in ECM
When a DTC is stored in ECM and MIL is ON, a permanent DTC is erased with MIL shutoff if the same mal-
function is not detected after performing the drivi ng pattern for MIL shutoff three times in a raw.
PBIB2244E
For normal acceleration in low altitude areas
[less than 1,219 m (4,000 ft)]: For quick acceleration in low alti-
tude areas and high altitude areas [over 1,219 m (4,000 ft)]:
Gear change ACCEL shift positi on [km/h (MPH)] CRUISE shift point [km/h (MPH)]km/h (MPH)
1st to 2nd 15 (9) 21 (13) 15 (9)
2nd to 3rd 25 (16) 38 (24)30 (19)
3rd to 4th 40 (25) 55 (34)45 (28)
4th to 5th 45 (28) 74 (46)50 (31)
Revision: January 20102010 Versa
ENGINE CONTROL SYSTEM SYMPTOMSEC-485
< SYMPTOM DIAGNOSIS > [HR16DE]
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1 - 6: The numbers refer to the order of inspection.
(continued on next table)
SYSTEM — ENGINE MECHANICAL & OTHER
Crankshaft position sensor (POS) circuit 2 2
EC-257
Camshaft position sensor (PHASE) circuit 3 2EC-262
Vehicle speed signal circuit2 3 33EC-341
ECM 22333333333 EC-347EC-349
Intake valve timing control solenoid valve cir-
cuit32 13223 3
EC-138
PNP signal circuit3 3 3 33EC-356
Refrigerant pressure sensor circuit 233 4 EC-450
Electrical load signal circuit 3EC-421
Air conditioner circuit 223333333 3 2 MTC-23
ABS actuator and electric unit (control unit)4 BRC-10
SYMPTOM
Reference
page
HARD/NO START/RESTART (EXCP. HA)
ENGINE STALL
HESITATION/SURGING/FLAT SPOT
SPARK KNOCK/DETONATION
LACK OF POWER/POOR ACCELERATION
HIGH IDLE/LOW IDLE
ROUGH IDLE/HUNTING
IDLING VIBRATION
SLOW/NO RETURN TO IDLE
OVERHEATS/WATER TEMPERATURE HIGH
EXCESSIVE FUEL CONSUMPTION
EXCESSIVE OIL CONSUMPTION
BATTERY DEAD (UNDER CHARGE)
Warranty symptom code AA AB AC AD AE AF AG AH AJ AK AL AM HA
Revision: January 20102010 Versa
EC-502
< SERVICE DATA AND SPECIFICATIONS (SDS) [HR16DE]
SERVICE DATA AND SPECIFICATIONS (SDS)
SERVICE DATA AND SPECIFICATIONS (SDS)
SERVICE DATA AND SPECIFICATIONS (SDS)
Idle SpeedINFOID:0000000005398655
*: Under the following conditions
• A/C switch: OFF
• Electric load: OFF (Lights, heater fan & rear window defogger)
• Steering wheel: Kept in straight-ahead position
Ignition TimingINFOID:0000000005398656
*: Under the following conditions
• A/C switch: OFF
• Electric load: OFF (Lights, heater fan & rear window defogger)
• Steering wheel: Kept in straight-ahead position
Calculated Load ValueINFOID:0000000005398657
Mass Air Flow SensorINFOID:0000000005398658
*: Engine is warmed up to normal operating temperature and running under no load.Transmission
ConditionSpecification
A/T No load* (in P or N position) 700 ± 50 rpm
M/T No load* (in Neutral position) 650 ± 50 rpm
Transmission ConditionSpecification
A/T No load* (in P or N position) 6 ± 5 °BTDC
M/T No load* (in Neutral position) 6 ± 5 °BTDC
Condition Specification (Using CONSULT-III or GST)
At idle 10 – 35 %
At 2,500 rpm 10 – 35 %
Supply voltageBattery voltage (11 – 14 V)
Output voltage at idle 0.9 – 1.3V*
Mass air flow (Using CONSULT-III or GST) 1.0 – 4.0 g·m/sec at idle*
2.0 – 10.0 g·m/sec at 2,500 rpm*
Revision: January 20102010 Versa
ENGINE CONTROL SYSTEMEC-517
< SERVICE INFORMATION > [MR18DE]
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*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 mass air flow sensor.
VARIOUS FUEL INJECTION INCREASE/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 sensor Engine 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: January 20102010 Versa
EC-518
< SERVICE INFORMATION >[MR18DE]
ENGINE CONTROL SYSTEM
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 t he 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 mixt ure ratio signal transmitted 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 r eduction 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 carri ed out long-term to compensate for continual deviation
of the short term fuel trim from t he 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 cycle 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: January 20102010 Versa
ENGINE CONTROL SYSTEMEC-519
< SERVICE INFORMATION > [MR18DE]
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This system is used when the engine is being started and/or if the fail-safe system (CPU) is operating.
FUEL SHUT-OFF
Fuel to each cylinder is cut off during deceleration, operation of the engine at excessively high speeds or oper-
ation of the vehicle at excessively high speeds.
Electronic Ignition (EI) SystemINFOID:0000000005532382
INPUT/OUTPUT SIGNAL CHART
*1: This signal is sent to the ECM through CAN communication line.
*2: ECM determines the start signal status by the signals of engine speed and battery voltage.
SYSTEM DESCRIPTION
Firing order: 1 - 3 - 4 - 2
The ignition timing is controlled by the ECM to maintain the best air-fuel ratio for every running condition of the
engine. The ignition timing data is stored in the ECM.
The ECM receives information such as the injecti
on pulse width and camshaft position sensor (PHASE) sig-
nal. Computing this information, ignition si gnals are transmitted to the power transistor.
During the following conditions, the ignition timing is revi sed by the ECM according to the other data stored in
the ECM.
• At starting
• During warm-up
•At idle
• At low battery voltage
• During acceleration
The knock sensor retard system is designed only for emergencies. The basic ignition timing is programmed
within the anti-knocking zone, if recommended fuel is used under dry conditions. The retard system does not
operate under normal driving conditions. If engine knocking occurs, the knock sensor monitors the condition.
The signal is transmitted to the ECM. The ECM retards the ignition timing to eliminate the knocking condition.
Fuel Cut Control (at No Load and High Engine Speed)INFOID:0000000005532383
INPUT/OUTPUT SIGNAL CHART
Sensor Input Signal to ECMECM functionActuator
Crankshaft position sensor (POS) Engine speed*
2
Piston position
Ignition timing
controlPower transistor
Camshaft position sensor (PHASE)
Mass air flow sensor
Amount of intake air
Engine coolant temperature sensor Engine coolant temperature
Throttle position sensor Throttle position
Accelerator pedal position sensor Accelerator pedal position
Battery Battery voltage*
2
Knock sensor Engine knocking
Park/neutral position (PNP) signal Gear position
ABS actuator and electric unit (control unit) Vehicle speed*
1Combination meter
SensorInput Signal to ECMECM functionActuator
Park/neutral position (PNP) signal Neutral position
Fuel cut control Fuel injector
Accelerator pedal position sensor
Accelerator pedal position
Engine coolant temperature sensor Engine coolant temperature
Crankshaft position sensor (POS)
Camshaft position sensor (PHASE) Engine speed
ABS actuator and electric unit (control unit) Vehicle speed*
Combination meter
Revision: January 20102010 Versa
AIR CONDITIONING CUT CONTROLEC-521
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AIR CONDITIONING
CUT CONTROL
Input/Output Signal ChartINFOID:0000000005532384
*1: This signal is sent to the ECM through CAN communication line.
*2: ECM determines the start signal status by the signals of engine speed and battery voltage.
System DescriptionINFOID:0000000005532385
This system improves engine operation when the air conditioner is used.
Under the following conditions, the air conditioner is turned off.
• When the accelerator pedal is fully depressed.
• When cranking the engine.
• At high engine speeds.
• When the engine coolant temperature becomes excessively high.
• When operating power steering during low engine speed or low vehicle speed.
• When engine speed is excessively low.
• When refrigerant pressure is excessively low or high.
Sensor Input Signal to ECMECM functionActuator
Air conditioner switch Air conditioner ON signal*
1
Air conditioner
cut controlAir conditioner relay
Accelerator pedal position sensor
Accelerator pedal position
Crankshaft position sensor (POS)
Camshaft position sensor (PHASE) Engine speed*
2
Engine coolant temperature sensor
Engine coolant temperature
Battery Battery voltage*
2
Refrigerant pressure sensorRefrigerant pressure
EPS control unit Power steering operation*
1
ABS actuator and electric unit (control unit)
Vehicle speed*1
Combination meter
Revision: January 20102010 Versa