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System -- Basic Engine Control System

SYMPTOM

Reference

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 pump circuit

1

1

2

3

2

2

2

3

2

Component Function Check

Fuel pressure regulator system

3

3

4

4

4

4

4

4

4

4

Work Procedure

Direct fuel injector circuit

1

1

2

3

2

2

2

2

Diagnosis Procedure

Port fuel injector circuit

1

1

2

3

2

2

2

2

Diagnosis Procedure

Evaporative emission system

3

3

4

4

4

4

4

4

4

4

Inspection 

Fuel rail pressure sensor circuit

1

1

2

2

2

2

2

2

DTC Description

High pressure fuel pump circuit

4

3

Component Function Check

Air

Positive crankcase ventilation system

3

3

4

4

4

4

4

4

4

4

1

Inspection 

Incorrect idle speed adjustment

1

1

1

1

1

Work Procedure

Electric throttle control actuator

1

1

2

3

3

2

2

2

2

2

2

DTC Description ,

DTC Description

Intake manifold runner control valve circuit

4

4

DTC Description

Ignition

Incorrect ignition timing adjustment

3

3

1

1

1

1

1

1

Work Procedure

Ignition circuit

1

1

2

2

2

2

2

2

Component Function Check

Main power supply and ground circuit

2

2

3

3

3

3

3

2

3

Diagnosis Procedure

Main power supply and ground circuit

1

1

2

2

2

2

2

2

Diagnosis Procedure

Mass air flow sensor circuit

2

Engine coolant temperature sensor circuit

3

3

3

DTC Description

Air fuel ratio (A/F) sensor 1 circuit

DTC Description ,

DTC Description ,

DTC Description

Throttle position sensor circuit

2

2

DTC Description ,

DTC Description ,

DTC Description ,

DTC Description ,

DTC Description

Accelerator pedal position sensor circuit

3

2

1

DTC Description ,

DTC Description ,

DTC Description

Heated oxygen sensor 2 circuit

6

6

6

6

5

Knock sensor circuit

2

3

DTC Description

Engine oil temperature sensor circuit

4

2

3

DTC Description

Engine oil pressure sensor circuit

4

4

3

3

3

3

Crankshaft position sensor circuit

2

2

DTC Description

Intake camshaft position sensor (PHASE) circuit

3

2

DTC Description

Turbocharger boost sensor circuit

3

3

Manifold absolute pressure sensor circuit

2

Vehicle speed signal circuit

2

3

3

3

DTC Description

ECM

2

2

3

3

3

3

3

3

3

3

3

DTC Description

Electric Intake valve timing control module circuit

3

3

3

Exhaust valve timing control solenoid valve circuit

3

2

1

3

2

2

3

3

DTC Description ,

DTC Description

Electric Intake valve timing control actuator circuit

3

Exhaust camshaft position sensor circuit

5

5

5

5

5

5

5

5

DTC Description

Transmission range switch

3

3

3

3

3

DTC Description

Intake manifold runner control valve motor circuit

5

4

4

2

4

4

4

4

Intake manifold runner control valve position sensor circuit

Turbocharger bypass control valve circuit

3

3

Electric wastegate valve circuit

1

Electric recirculation valve circuit

1

Refrigerant pressure sensor circuit

2

3

3

4

Component Function Check

Cooling fan control module circuit

5

5

5

5

5

5

5

5

4

5

Battery current sensor circuit

4

5

5

Electrical load signal circuit

3

Component Function Check

Air conditioner circuit

2

2

3

3

3

3

3

3

3

3

2

Work Flow

ABS actuator and electric unit (control unit)

4

Work Flow

VCR System

5

1

2

3

4

6

1 - 6: The numbers refer to the order of inspection.

(continued on next table)