EC-22
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ENGINE CONTROL SYSTEM
Engine Control Comp onent Parts Location
INFOID:0000000003771302
1. ECM 2. Battery current sensor 3. Power steering pressure sensor
4. Ignition coil (with power transistor)
and spark plug (bank 2) 5. Refrigerant pressure sensor 6. Intake valve timing control position
sensor (bank 2)
7. Intake valve timing control solenoid valve (bank 2) 8. Engine coolant temperature sensor 9. Electric throttle control actuator
10. Intake valve timing control position sensor (bank 1) 11. Intake valve timing control solenoid
valve (bank 1) 12. Cooling fan motor
13. Camshaft position sensor (PHASE) 14. I gnition coil (with power transistor)
and spark plug (bank 1) 15. Mass air flow sensor (with intake air
temperature sensor)
16. A/F sensor 1 (bank 1) 17. EVAP service port 18. Fuel injector (bank 1)
19. Knock sensor (bank 1) 20. EVAP canister purge volume control solenoid valve21. Knock sensor (bank 2)
22. Fuel injector (bank 2) 23. A/F sensor 1 (bank 2) 24. IPDM E/R
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ENGINE CONTROL SYSTEMEC-23
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1. Body ground (view with battery re-
moved) 2. Body ground (view with battery re-
moved) 3. Body ground
4. No. 1 ignition coil 5. Engine ground 6. Mass air flow sensor (with intake air temperature sensor)
7. IPDM E/R 8. Battery 9. Radiator hose
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ENGINE CONTROL SYSTEMEC-25
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1. EVAP canister purge volume control
solenoid valve (view with engine
cover removed) 2. EVAP service port (view with engine
cover removed) 3. Crankshaft position sensor (POS)
(view from under the vehicle)
4. Engine oil pan (view from under the vehicle) 5. Condenser-1 6. Brake fluid reservoir
7. EVAP canister (view with fuel tank removed) 8. EVAP control system pressure sen-
sor (view with fuel tank removed) 9. EVAP canister vent control valve
(view with fuel tank removed)
10. Rear suspension member (view with fuel tank removed) 11. Refrigerant pressure sensor (view
with front grille removed) 12. Intake valve timing control position
sensor (bank 2) (view with engine
cover and intake air duct removed)
13. Intake valve timing control position sensor (bank 1) (view with engine
cover and intake air duct removed) 14. Intake valve timing control solenoid
valve (bank 2) (view with engine cov-
er and intake air duct removed) 15. Drive belt (view with engine cover
and intake air duct removed)
16. Radiator hose (view with engine cov- er and intake air duct removed) 17. Intake valve timing control solenoid
valve (bank 1) (view with engine cov-
er and intake air duct removed)
: Vehicle front
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EC-26
< FUNCTION DIAGNOSIS >[VK56DE]
ENGINE CONTROL SYSTEM
1. Knock sensor (bank 1) (view with en-
gine removed) 2. Knock sensor (bank 2) (view with en-
gine removed) 3. Battery current sensor
4. Power steering pressure sensor 5. Power steering fluid reservoir 6. Intake manifold
7. Engine coolant temperature sensor 8. Ignition coils (with power transistor) 9. Ignition coil (with power transistor)
10. Injector harness connectors (bank 2) 11. Injector harness connectors (bank 1) : Vehicle front
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ON BOARD DIAGNOSTIC (OBD) SYSTEMEC-71
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*: Leaving cooling fan OFF with CONSULT-III while engine is running may cause the engine to overheat.
DTC & SRT CONFIRMATION MODE
SRT STATUS Mode
For details, refer to
EC-456, "DTC Index".
SRT WORK SUPPORT Mode
This mode enables a technician to drive a vehicle to set the SRT while monitoring the SRT status.
DTC WORK SUPPORT Mode
TEST ITEM CONDITION JUDGEMENT CHECK 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
Selector lever: P or N
Cut off each 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 HI and OFF
using CONSULT-III. Cooling fan moves and stops. Harness and connectors
Cooling fan motor
IPDM E/R
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
Solenoid valve
FUEL/T TEMP
SEN Change the fuel tank temperature using CONSULT-III.
VENT CON-
TROL/V Ignition switch: ON
(Engine stopped)
Turn solenoid valve ON and OFF with the CONSULT-III and listen
to operating sound. Solenoid valve makes an operating
sound.
Harness and connectors
Solenoid valve
V/T ASSIGN AN-
GLE Engine: Return to the original
trouble condition
Change intake valve timing using
CONSULT-III. If trouble symptom disappears, see
CHECK ITEM.
Harness and connectors
Intake valve timing control sole-
noid valve
ALTERNATOR
DUTY Engine: Idle
Change duty ratio using CON-
SULT-III. Battery voltage changes. Harness and connectors
IPDM E/R
Alternator
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TROUBLE DIAGNOSIS - SPECIFICATION VALUEEC-77
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Check “A/F ALPHA-B1”, “A/F ALPHA-B2” for approximat
ely 1 minute because they may fluctuate. It is NG
if the indication is out of the SP value even a little.
OK or NG
OK >> GO TO 17.
NG (Less than the SP value)>>GO TO 2.
NG (More than the SP value)>>GO TO 3.
2.CHECK “B/FUEL SCHDL”
Select “B/FUEL SCHDL” in “SPEC” of “DATA MONITOR” m ode, and make sure that the indication is within the
SP value.
OK or NG
OK >> GO TO 4.
NG (More than the SP value)>>GO TO 19.
3.CHECK “B/FUEL SCHDL”
Select “B/FUEL SCHDL” in “SPEC” of “DATA MONITOR” m ode, and make sure that the indication is within the
SP value.
OK or NG
OK >> GO TO 6.
NG (More than the SP value)>>GO TO 6.
NG (Less than the SP value)>>GO TO 25.
4.CHECK “A/F ALPHA-B1”, “A/F ALPHA-B2”
1. Stop the engine.
2. Disconnect PCV hose, and then plug it.
3. Start engine.
4. Select “A/F ALPHA-B1”, “A/F AL PHA-B2” in “SPEC” of “DATA MONITOR” mode, and make sure that the
each indication is within the SP value.
OK or NG
OK >> GO TO 5.
NG >> GO TO 6.
5.CHANGE ENGINE OIL
1. Stop the engine.
2. Change engine oil. NOTE:
This symptom may occur when a large amount of gas oline is mixed with engine oil because of driving
conditions (such as when engine oil temperature does not rise enough since a journey distance is too
short during winter). The symptom will not be detect ed after changing engine oil or changing driving con-
dition.
>>INSPECTION END
6.CHECK FUEL PRESSURE
Check fuel pressure. (Refer to EC-487, "Fuel Pressure Check"
.)
OK or NG
OK >> GO TO 9.
NG (Fuel pressure is too high)>>Replace fuel pressure regulator, refer to EC-487, "Fuel Pressure Check"
.
GO TO 8.
NG (Fuel pressure is too low)>>GO TO 7.
7.DETECT MALFUNCTIONING PART
1. Check the following.
- Clogged and bent fuel hose and fuel tube
- Clogged fuel filter
- Fuel pump and its circuit (Refer to EC-487, "Fuel Pressure Check"
.)
2. If NG, repair or replace the malfunctioning part. (Refer to EC-487, "Fuel Pressure Check"
.)
If OK, replace fuel pressure regulator.
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EC-78
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TROUBLE DIAGNOSIS - SPECIFICATION VALUE
>> GO TO 8.
8.CHECK “A/F ALPHA-B1”, “A/F ALPHA-B2”
1. Start engine.
2. Select “A/F ALPHA-B1”, “A/F AL PHA-B2” in “SPEC” of “DATA MONITOR” mode, and make sure that the
each indication is within the SP value.
OK or NG
OK >> INSPECTION END
NG >> GO TO 9.
9.PERFORM POWER BALANCE TEST
1. Perform “POWER BALANCE” in “ACTIVE TEST” mode.
2. Make sure that the each cylinder produces a momentary engine speed drop.
OK or NG
OK >> GO TO 12.
NG >> GO TO 10.
10.DETECT MALFUNCTIONING PART
1. Check the following.
- Ignition coil and its circuit (Refer to EC-404, "Diagnosis Procedure"
.)
- Fuel injector and its circuit (Refer to EC-392, "Diagnosis Procedure"
.)
- Intake air leakage
- Low compression pressure (Refer to EM-23, "Checking Compression Pressure"
.)
2. If NG, repair or replace the malfunctioning part.
If OK, replace fuel injector. (It may be caus ed by leakage from fuel injector or clogging.)
>> GO TO 11.
11 .CHECK “A/F ALPHA-B1”, “A/F ALPHA-B2”
1. Start engine.
2. Select “A/F ALPHA-B1”, “A/F AL PHA-B2” in “SPEC” of “DATA MONITOR” mode, and make sure that the
each indication is within the SP value.
OK or NG
OK >> INSPECTION END
NG >> GO TO 12.
12.CHECK A/F SENSOR 1 FUNCTION
Perform all DTC Confirmation Procedure related with A/F sensor 1.
For DTC P0130, P0150, refer to EC-136, "DTC Confirmation Procedure"
.
For DTC P0131, P0151, refer to EC-140, "DTC Confirmation Procedure"
.
For DTC P0132, P0132, refer to EC-143, "DTC Confirmation Procedure"
.
For DTC P0133, P0153, refer to EC-146, "DTC Confirmation Procedure"
.
For DTC P2A00, P2A03, refer to EC-377, "DTC Confirmation Procedure"
.
OK or NG
OK >> GO TO 15.
NG >> GO TO 13.
13.CHECK A/F SENSOR 1 CIRCUIT
Perform Diagnostic Procedure according to corresponding DTC.
>> GO TO 14.
14.CHECK “A/F ALPHA-B1”, “A/F ALPHA-B2”
1. Start engine.
2. Select “A/F ALPHA-B1”, “A/F AL PHA-B2” in “SPEC” of “DATA MONITOR” mode, and make sure that the
each indication is within the SP value.
OK or NG
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OK >>
INSPECTION END
NG >> GO TO 15.
15.DISCONNECT AND RECONNECT ECM HARNESS CONNECTOR
1. Stop the engine.
2. Disconnect ECM harness connector. Check pin term inal and connector for damage, and then reconnect it.
>> GO TO 16.
16.CHECK “A/F ALPHA-B1”, “A/F ALPHA-B2”
1. Start engine.
2. Select “A/F ALPHA-B1”, “A/F AL PHA-B2” in “SPEC” of “DATA MONITOR” mode, and make sure that the
each indication is within the SP value.
OK or NG
OK >> INSPECTION END
NG >> Detect malfunctioning part according to EC-475, "Symptom Matrix Chart"
.
17.CHECK “B/FUEL SCHDL”
Select “B/FUEL SCHDL” in “SPEC” of “DATA MONITOR” m ode, and make sure that the indication is within the
SP value.
OK or NG
OK >> INSPECTION END
NG (More than the SP value)>>GO TO 18.
NG (Less than the SP value)>>GO TO 25.
18.DETECT MALFUNCTIONING PART
1. Check for the cause of large engine friction. Refer to the following.
- Engine oil level is too high
- Engine oil viscosity
- Belt tension of power steering, alternator, A/C compressor, etc. is excessive
- Noise from engine
- Noise from transmission, etc.
2. Check for the cause of insufficient combustion. Refer to the following.
- Valve clearance malfunction
- Intake valve timing control function malfunction
- Camshaft sprocket installation malfunction, etc.
>> Repair or replace malfunctioning part, and then GO TO 30.
19.CHECK INTAKE SYSTEM
Check for the cause of uneven air flow through mass air flow sensor. Refer to the following.
Crushed air ducts
Malfunctioning seal of air cleaner element
Uneven dirt of air cleaner element
Improper specification of intake air system
OK or NG
OK >> GO TO 21.
NG >> Repair or replace malfunctioning part, and then GO TO 20.
20.CHECK “A/F ALPHA-B1”, “A/F ALPHA-B2”, AND “B/FUEL SCHDL”
Select “A/F ALPHA-B1”, “A/F ALPHA-B2”, and “B/F UEL SCHDL” in “SPEC” of “DATA MONITOR” mode, and
make sure that the each indication is within the SP value.
OK or NG
OK >> INSPECTION END
NG (“B/FUEL SCHDL” is more, “A/F ALPHA-B1”, “A /F ALPHA-B2” are less than the SP value)>>GO TO 21.
21.DISCONNECT AND RECONNECT MASS AIR FLOW SENSOR HARNESS CONNECTOR
1. Stop the engine.
Revision: December 20092009 QX56