EC-420
[QG (WITHOUT EURO-OBD)]
ENGINE CONTROL SYSTEM
SYSTEM DESCRIPTION
The ignition timing is controlled by the ECM to maintain the best air-
fuel ratio for every running condition of the engine. The ignition tim-
ing data is stored in the ECM. This data forms the map shown.
The ECM receives information such as the injection pulse width and
camshaft position sensor signal. Computing this information, ignition
signals are transmitted to the power transistor.
e.g., N: 1,800 rpm, Tp: 1.50 msec
A°BTDC
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.
Air Conditioning Cut ControlEBS00KEE
INPUT/OUTPUT SIGNAL CHART
*1: These signals are sent to the ECM through CAN communication line.
*2: The ECM determines the start signal status by the signals of engine speed and battery voltage.
SYSTEM DESCRIPTION
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.
SEF742M
Sensor Input Signal to ECM ECM function Actuator
Air conditioner switch
*1Air conditioner “ON” signal
Air conditioner
cut controlAir conditioner relay Throttle position sensor Throttle valve opening angle
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
Power steering pressure sensor Power steering operation
Vehicle speed signal
*1Vehicle speed
EC-422
[QG (WITHOUT EURO-OBD)]
ENGINE CONTROL SYSTEM
Ty p e 1
SYSTEM DIAGRAM
INPUT/OUTPUT SIGNAL CHART
T: Transmit R: Receive
SEL825Y
Signals ECM TCMSmart entrance
control unitCombination meter
Engine speed signal T R
Brake switch signal R T
Rear window defogger signal R T
Heater fan switch signal R T
Air conditioner switch signal R T
MI signal T R
Current gear position signal T R
Engine coolant temperature signal T R
Fuel consumption signal T R
Vehicle speed signal R T
Seat belt reminder signalRT
Headlamp switch signalTR
Flashing indicator signalTR
Engine cooling fan speed signal T R
Child lock indicator signalTR
Door switches state signalTR
A/C compressor signal T R
Accelerator pedal position signal T R
Output shaft revolution signal R T
OD OFF switch signal R T
OD OFF indicator signal T R
A/T self-diagnosis signal R T
ENGINE CONTROL SYSTEM
EC-423
[QG (WITHOUT EURO-OBD)]
C
D
E
F
G
H
I
J
K
L
MA
EC
Ty p e 2
SYSTEM DIAGRAM
INPUT/OUTPUT SIGNAL CHART
T: Transmit R: Receive
SEL826Y
Signals ECMSmart entrance control
unitCombination meter
Engine speed signal T R
Rear window defogger signal R T
Heater fan switch signal R T
Air conditioner switch signal R T
MI signal T R
Engine coolant temperature signal T R
Fuel consumption signal T R
Vehicle speed signal R T
Seat belt reminder signal R T
Headlamp switch signal T R
Flashing indicator signal T R
Engine cooling fan speed signal T R
Child lock indicator signal T R
Door switches state signal T R
A/C compressor signal T R
BASIC SERVICE PROCEDURE
EC-425
[QG (WITHOUT EURO-OBD)]
C
D
E
F
G
H
I
J
K
L
MA
EC
3. Check ignition timing.
Accelerator Pedal Released Position LearningEBS00KEI
DESCRIPTION
“Accelerator Pedal Released Position Learning” is an operation to learn the fully released position of the accel-
erator pedal by monitoring the accelerator pedal position sensor output signal. It must be performed each time
harness connector of accelerator pedal position sensor or ECM is disconnected.
OPERATION PROCEDURE
1. Make sure that accelerator pedal is fully released.
2. Turn ignition switch “ON” and wait at least 2 seconds.
3. Turn ignition switch “OFF” wait at least 10 seconds.
4. Turn ignition switch “ON” and wait at least 2 seconds.
5. Turn ignition switch “OFF” wait at least 10 seconds.
Throttle Valve Closed Position LearningEBS00KEJ
DESCRIPTION
“Throttle Valve Closed Position Learning” is an operation to learn the fully closed position of the throttle valve
by monitoring the throttle position sensor output signal. It must be performed each time harness connector of
electric throttle control actuator or ECM is disconnected.
OPERATION PROCEDURE
1. Make sure that accelerator pedal is fully released.
2. Turn ignition switch “ON”.
3. Turn ignition switch “OFF” wait at least 10 seconds.
Make sure that throttle valve moves during above 10 seconds by confirming the operating sound.
Idle Air Volume LearningEBS00KEK
DESCRIPTION
“Idle Air Volume Learning” is an operation to learn the idle air volume that keeps each engine within the spe-
cific range. It must be performed under any of the following conditions:
●Each time electric throttle control actuator or ECM is replaced.
●Idle speed or ignition timing is out of specification.
PREPARATION
Before performing “Idle Air Volume Learning”, make sure that all of the following conditions are satisfied.
Learning will be cancelled if any of the following conditions are missed for even a moment.
●Battery voltage: More than 12.9V (At idle)
●Engine coolant temperature: 70 - 95°C (158 - 203°F)
●PNP switch: ON
●Electric load switch: OFF
(Air conditioner, headlamp, rear window defogger)
On vehicles equipped with daytime light systems, set lighting switch to the 1st position to light
only small lamps.
●Steering wheel: Neutral (Straight-ahead position)
●Vehicle speed: Stopped
SEF166Y
TROUBLE DIAGNOSIS
EC-443
[QG (WITHOUT EURO-OBD)]
C
D
E
F
G
H
I
J
K
L
MA
EC
Basic InspectionEBS00KEU
1.INSPECTION START
1. Check service records for any recent repairs that may indicate a related malfunction, or a current need for
scheduled maintenance.
2. Open engine hood and check the following:
–Harness connectors for improper connections
–Wiring harness for improper connections, pinches and cut
–Vacuum hoses for splits, kinks and improper connections
–Hoses and ducts for leaks
–Air cleaner clogging
–Gasket
3. Confirm that electrical or mechanical loads are not applied.
–Headlamp switch is OFF.
–Air conditioner switch is OFF.
–Rear window defogger switch is OFF.
–Steering wheel is in the straight-ahead position, etc.
4. Start engine and warm it up until engine coolant temperature
indicator points the middle of gauge.
Ensure engine stays below 1,000 rpm.
5. Run engine at about 2,000 rpm for about 2 minutes under no-
load.
6. Make sure that no DTC is displayed with CONSULT-II or ECM.
OK or NG
OK >> GO TO 3.
NG >> GO TO 2.
2.REPAIR OR REPLACE
Repair or replace components as necessary according to corresponding “Diagnostic Procedure”.
>> GO TO 3.
SEF983U
SEF976U
SEF977U
TROUBLE DIAGNOSIS
EC-449
[QG (WITHOUT EURO-OBD)]
C
D
E
F
G
H
I
J
K
L
MA
EC
1 - 6: The numbers refer to the order of inspection.
(continued on next page)
SYSTEM — ENGINE MECHANICAL & OTHER
ECM 22333333333EC-568,
EC-571
Intake valve timing control solenoid valve cir-
cuit332 13223 3EC-683
PNP switch circuit 3 33333 3EC-689
Refrigerant pressure sensor circuit 2 3 3 3 3 4EC-705
Electrical load signal circuit 3 3 3 3EC-710
Air conditioner circuit223333333 3 2AT C - 2 9
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
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
Fuel Fuel tank
5
5FE-4
Fuel piping 5 5 5 5 5 5 FE-4
Vapor lock—
Valve deposit
555555 5—
Poor fuel (Heavy weight gaso-
line, Low octane)—
EC-466
[QG (WITHOUT EURO-OBD)]
TROUBLE DIAGNOSIS
ENGINE CONTROL COMPONENT PARTS/CONTROL SYSTEMS APPLICATION
X: Applicable
*1: This item includes 1st trip DTCs.
*2: This mode includes 1st trip freeze frame data or freeze frame data. The items appear on CONSULT-II screen in freeze frame data
mode only if a 1st trip DTC or DTC is detected. For details, refer to EC-468
.
CONSULT-II INSPECTION PROCEDURE
1. Turn ignition switch OFF.
ItemDIAGNOSTIC TEST MODE
WORK
SUPPORTSELF-DIAGNOSTIC
RESULTS
DATA
MONI-
TORDATA
MONI-
TOR
(SPEC)ACTIVE
TEST DTC*1FREEZE
FRAME
DATA
*2
ENGINE CONTROL COMPONENT PARTS
INPUT
Crankshaft position sensor (POS)××××
Camshaft position sensor (PHASE)×××
Mass air flow sensor×××
Engine coolant temperature sensor×××××
Heated oxygen sensor 1×××
Heated oxygen sensor 2×××
Vehicle speed signal×××
Accelerator pedal position sensor×××
Throttle position sensor×××
Intake air temperature sensor××
Knock sensor×
Refrigerant pressure sensor××
Closed throttle position switch (accelerator
pedal position sensor signal)××
Air conditioner switch××
Park/neutral position (PNP) switch××
Stop lamp switch×××
Power steering pressure sensor××
Battery voltage××
Electrical load signal××
ENGINE CONTROL COMPONENT PARTS
OUTPUT
Injectors×× ×
Power transistor (Ignition timing)×× ×
Throttle control motor relay×××
Throttle control motor×
EVAP canister purge volume control sole-
noid valve×× ×
Air conditioner relay××
Fuel pump relay××××
Cooling fan relay××××
Heated oxygen sensor 1 heater××
Heated oxygen sensor 2 heater××
Intake valve timing control solenoid valve×× ×
Calculated load value×××
EC-470
[QG (WITHOUT EURO-OBD)]
TROUBLE DIAGNOSIS
THRTL SEN 1 [V]××●The throttle position sensor signal volt-
age is displayed.
THRTL SEN 2 [V]×
INT/A TEMP SE
[°C] or [°F]××
●The intake air temperature (determined
by the signal voltage of the intake air
temperature sensor) is indicated.
START SIGNAL
[ON/OFF]××
●Indicates [ON/OFF] condition of the
starter signal computed from the signals
of the crankshaft position sensor (POS),
camshaft position sensor (PHASE) and
battery voltage.
●After starting the engine, [OFF] is
displayed regardless of the starter
signal.
CLSD THL POS
[ON/OFF]××
●Indicates idle position [ON/OFF] com-
puted by ECM according to the acceler-
ator pedal position sensor signal.
AIR COND SIG
[ON/OFF]××
●Indicates [ON/OFF] condition of the air
conditioner switch as determined by the
air conditioner signal.
P/N POSI SW
[ON/OFF]××
●Indicates [ON/OFF] condition from the
park/neutral position (PNP) switch sig-
nal.
PW/ST SIGNAL
[ON/OFF]××
●[ON/OFF] condition of the power steer-
ing oil pressure switch as determined by
the power steering oil pressure signal is
indicated.
LOAD SIGNAL
[ON/OFF]××
●Indicates [ON/OFF] condition from the
electrical load signal.
ON ... Rear window defogger switch is
ON and/or lighting switch is in 2nd posi-
tion.
OFF ... Both rear window defogger
switch and lighting switch are OFF.
IGNITION SW
[ON/OFF]×
●Indicates [ON/OFF] condition from igni-
tion switch.
HEATER FAN SW
[ON/OFF]×
●Indicates [ON/OFF] condition from the
heater fan switch signal.
BRAKE SW
[ON/OFF]×
●Indicates [ON/OFF] condition from the
stop lamp switch signal.
INJ PULSE-B1
[msec]×
●Indicates the actual fuel injection pulse
width compensated by ECM according
to the input signals.●When the engine is stopped, a
certain computed value is indi-
cated.
IGN TIMING
[BTDC]×
●Indicates the ignition timing computed
by ECM according to the input signals.●When the engine is stopped, a
certain value is indicated.
CAL/LD VALUE [%]
●“Calculated load value” indicates the
value of the current airflow divided by
peak airflow.
MASS AIRFLOW
[g·m/s]
●Indicates the mass airflow computed by
ECM according to the signal voltage of
the mass air flow sensor. Monitored item
[Unit]ECM
INPUT
SIG-
NALSMAIN
SIG-
NALSCAN
DIAG
SUP-
PORT
MNTRDescription Remarks