
EC-8
Engine Coolant Temperature Sensor  ....................548
Air Fuel Ratio (A/F) Sensor 1 Heater  .....................549
Heated Oxygen sensor 2 Heater  ...........................549
Crankshaft Position Sensor (POS)  ........................549
Camshaft Position Sensor (PHASE)  .....................549
Throttle Control Motor  ...........................................549
Fuel Injector  ..........................................................549
Fuel Pump .............................................................549 

EC-18
< SERVICE INFORMATION >
PRECAUTIONS
•Before replacing ECM, perform “ECM Terminals and Refer-
ence Value” inspection and make sure ECM functions prop-
erly. Refer to EC-102, "
ECM Terminal and Reference Value".
•Handle mass air flow sensor carefully to avoid damage.
•Do not disassemble mass air flow sensor.
•Do not clean mass air flow sensor with any type of detergent.
•Do not disassemble electric throttle control actuator.
•Even a slight leak in the air intake system can cause serious
incidents.
•Do not shock or jar the camshaft position sensor (PHASE),
crankshaft position sensor (POS).
•After performing each TROUBLE DIAGNOSIS, perform DTC
Confirmation Procedure or Overall Function Check.
The DTC should not be displayed in the DTC Confirmation
Procedure if the repair is completed. The Overall Function
Check should be a good result if the repair is completed.
•When measuring ECM signals with a circuit tester, never allow
the two tester probes to contact.
Accidental contact of probes will cause a short circuit and
damage the ECM power transistor.
•Do not use ECM ground terminals when measuring input/out-
put voltage. Doing so may result in damage to the ECM's tran-
sistor. Use a ground other than ECM terminals, such as the
ground.
•Do not operate fuel pump when there is no fuel in lines.
•Tighten fuel hose clamps to the specified torque.
-Fuel level sensor unit and fuel pump (1)
-Fuel pressure regulator (2)
-Fuel level sensor (3)
-Fuel tank temperature sensor (4)
MEF040D
SEF217U
SEF348N
BBIA0704E 

ENGINE CONTROL SYSTEM
EC-23
< SERVICE INFORMATION >
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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). The 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 the 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 deceleration
• During high engine speed operation
MIXTURE RATIO FEEDBACK CONTROL (CLOSED LOOP CONTROL)
The mixture ratio feedback system provides the best air/fuel mixture ratio for driveability and emission control.
The three way catalyst (manifold) can then better reduce CO, HC and NOx emissions. This system uses air
Sensor Input Signal to ECM ECM function Actuator
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) switch 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
Wheel sensor
Vehicle speed*2
PBIB3020E 

ENGINE CONTROL SYSTEM
EC-25
< SERVICE INFORMATION >
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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:0000000001702556
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 injection pulse width and camshaft position sensor (PHASE) sig-
nal. Computing this information, ignition signals are transmitted to the power transistor.
During the following conditions, the ignition timing is revised 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:0000000001702557
INPUT/OUTPUT SIGNAL CHART
*: This signal is sent to the ECM through CAN communication line.
SYSTEM DESCRIPTION
Sensor Input Signal to ECM ECM function Actuator
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) switch Gear position
Wheel sensor
Vehicle speed*
1
Sensor Input Signal to ECM ECM function Actuator
Park/neutral position (PNP) switch 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
Wheel sensor Vehicle speed* 

AIR CONDITIONING CUT CONTROL
EC-27
< SERVICE INFORMATION >
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AIR CONDITIONING CUT CONTROL
Input/Output Signal ChartINFOID:0000000001702558
*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:0000000001702559
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 ECM ECM function Actuator
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 sensor Refrigerant pressure
EPS control unit
Power steering operation*
1
Wheel sensor
Vehicle speed*1 

BASIC SERVICE PROCEDURE
EC-71
< SERVICE INFORMATION >
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 With CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Read idle speed in “DATA MONITOR” mode with CONSULT-II.
Refer to EC-73, "
Idle Speed and Ignition Timing Check".
 Without CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Check idle speed. Refer to EC-73, "
Idle Speed and Ignition Tim-
ing Check".
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-295
.
• Check camshaft position sensor (PHASE) and circuit.
Refer to EC-302
.
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-211, "
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-73, "
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-76, "
Accelerator Pedal Released Position Learning". 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)
SEF174Y
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 

BASIC SERVICE PROCEDURE
EC-73
< SERVICE INFORMATION >
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2. GO TO 4.
17.DETECT MALFUNCTIONING PART
Check the following.
• Check crankshaft position sensor (POS) and circuit.
Refer to EC-295
.
• Check camshaft position sensor (PHASE) and circuit.
Refer to EC-302
.
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 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-211, "
ECM Re-communicating Function".
>> GO TO 4.
19.INSPECTION END
Did you replace ECM, referring this Basic Inspection procedure?
Ye s  o r  N o
Ye s > > 1 . P e r f o r m  EC-75, "VIN Registration".
2.INSPECTION END
No >>INSPECTION END
Idle Speed and Ignition Timing CheckINFOID:0000000001702579
IDLE SPEED
 With CONSULT-II
Check idle speed in “DATA MONITOR” mode with CONSULT-II.
 With GST
Check idle speed in Service $01 with GST.
IGNITION TIMING
Any of following two methods may be used.
Method A
SEF058Y 

TROUBLE DIAGNOSIS
EC-87
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Fail-Safe ChartINFOID:0000000001702588
When the DTC listed below is detected, the ECM enters fail-safe mode and the MIL lights up.
Priority Detected items (DTC)
1 • U1000 U1001 CAN communication line
• U1010 CAN communication
• P0101 P0102 P0103 Mass air flow sensor
• P0112 P0113 P0127 Intake air temperature sensor
• 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 ECM
• P0643 Sensor power supply
• P0705 P0850 Park/neutral position (PNP) switch
• P1610 - P1615 NATS
• P2122 P2123 P2127 P2128 P2138 Accelerator pedal position sensor
2 • P0031 P0032 Air fuel ratio (A/F) sensor 1 heater
• P0037 P0038 Heated oxygen sensor 2 heater
• P0075 Intake valve timing control solenoid valve
• P0130 P0131 P0132 P0133 P2A00 Air fuel ratio (A/F) sensor 1
• P0137 P0138 P0139 Heated oxygen sensor 2
• P0441 EVAP control system purge flow monitoring
• P0443 P0444 P0445 EVAP canister purge volume control solenoid valve
• P0447 P0448 EVAP canister vent control valve
• P0451 P0452 P0453 EVAP control system pressure sensor
• P1217 Engine over temperature (OVERHEAT)
• P1805 Brake switch
• P2100 P2103 Throttle control motor relay
• P2101 Electric throttle control function
• P2118 Throttle control motor
3 • P0011 Intake valve timing control
• P0171 P0172 Fuel injection system function
• P0300 - P0304 Misfire
• P0420 Three way catalyst function
• P0442 P0456 EVAP control system (SMALL LEAK, VERY SMALL LEAK)
• P0455 EVAP control system (GROSS LEAK)
• P0506 P0507 Idle speed control system
• P0710 P0715 P0720 P0725 P0731 P0732 P0733 P0734 P0740 P0744 P0745 P0746 P0750 P0755 P0776 P0778 
P0840 P0845 P1705 P1740 P1760 P1777 P1778 A/T or CVT related sensors, solenoid valves and switches
• P1148 Closed loop control
• P1421 Cold start control
• P1564 ASCD steering switch
• P1572 ASCD brake switch
• P1574 ASCD vehicle speed sensor
• P1715 Turbine revolution sensor (A/T), Primary speed sensor (CVT)
• P2119 Electric throttle control actuator
DTC No. Detected items Engine operating condition in fail-safe mode
P0102
P0103Mass air flow sensor circuit Engine speed will not rise more than 2,400 rpm due to the fuel cut.