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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

Low pressure 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

Fuel injector circuit

1

1

2

3

2

2

2

2

Component Function Check

Evaporative emission system

3

3

4

4

4

4

4

4

4

4

System Description

FRP sensor circuit

1

1

2

2

2

2

2

2

DTC Description , DTC Description , DTC Description , DTC Description

High pressure fuel pump circuit

4

3

DTC Description

Air

Positive crankcase ventilation system

3

3

4

4

4

4

4

4

4

4

1

Positive Crankcase Ventilation

Incorrect idle speed adjustment

1

1

1

1

1

Inspection 

Electric throttle control actuator

1

1

2

3

3

2

2

2

2

2

2

DTC Description , DTC Description

Intake manifold runner control circuit

4

4

DTC Description , DTC Description

Ignition

Incorrect ignition timing adjustment

3

3

1

1

1

1

1

1

Inspection 

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

Mass air flow sensor circuit

1

1

2

2

2

2

2

2

DTC Description , DTC Description , DTC Description

Engine coolant temperature sensor circuit

3

3

3

DTC Description , DTC Description , DTC Description , DTC Description

Air fuel ratio (A/F) sensor 1 circuit

DTC Description , 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

DTC Description

Knock sensor circuit

2

3

DTC Description

Engine oil temperature sensor circuit

4

2

3

DTC Description , DTC Description

Engine oil pressure sensor circuit

4

4

3

3

3

3

DTC Description

Crankshaft position sensor circuit

2

2

DTC Description

Intake camshaft position sensor circuit

3

2

3

DTC Description , DTC Description

Exhaust camshaft position sensor circuit

2

2

3

3

3

Diagnosis Procedure , Diagnosis Procedure

Vehicle speed signal circuit

2

3

3

3

DTC Description

ECM

2

2

3

3

3

3

3

3

3

3

3

--

Electric intake valve timing control module circuit

3

3

3

Diagnosis Procedure , Diagnosis Procedure , Diagnosis Procedure , Diagnosis Procedure , Diagnosis Procedure

Electric intake valve timing control actuator circuit

3

Diagnosis Procedure , Diagnosis Procedure , Diagnosis Procedure , Diagnosis Procedure , Diagnosis Procedure , Diagnosis Procedure

Exhaust valve timing control solenoid valve circuit

2

2

2

2

2

2

DTC Description , DTC Description

PNP signal circuit

3

3

3

3

3

DTC Description

Refrigerant pressure sensor circuit

2

3

3

4

Component Function Check

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

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

(continued on next chart)