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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     INSPECTION 
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
Air Positive crankcase ventilation system 3 3 4 4 4 4 4 4 4   4 1   COMPONENT INSPECTION
Incorrect idle speed adjustment       1 1 1 1   1     SPECIAL REPAIR REQUIREMENT
Electric throttle control actuator 1 1 2 3 3 2 2 2 2   2   2 DTC LOGIC , DTC LOGIC
Ignition Incorrect ignition timing adjustment 3 3 1 1 1   1 1     1     SPECIAL REPAIR REQUIREMENT
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 LOGIC , DTC LOGIC
Engine coolant temperature sensor circuit 3 3 3       DTC LOGIC , DTC LOGIC
Air fuel ratio (A/F) sensor 1 circuit             DTC LOGIC , DTC LOGIC , DTC LOGIC , DTC LOGIC , DTC LOGIC
Throttle position sensor circuit     2 2       DTC LOGIC , DTC LOGIC , DTC LOGIC , DTC LOGIC , DTC LOGIC
Accelerator pedal position sensor circuit     3 2 1             DTC LOGIC , DTC LOGIC , DTC LOGIC
Knock sensor circuit     2               3     DTC LOGIC
Engine oil temperature sensor     4   1           3     DTC LOGIC , DTC LOGIC
Crankshaft position sensor (POS) circuit 2 2                       DTC LOGIC
Camshaft position sensor (PHASE) circuit 3 2                       DTC LOGIC
Vehicle speed signal circuit   2 3   3           3     DTC LOGIC
Power steering pressure sensor circuit   2         3 3           DTC LOGIC
ECM 2 2 3 3 3 3 3 3 3 3 3     DTC LOGIC , DTC LOGIC
Intake valve timing control solenoid valve circuit   3 2   1 3 2 2 3   3     DTC LOGIC
VVEL control module 3   4 4 3                 DTC LOGIC , DTC LOGIC
VVEL actuator motor 3   4 4 3                 DTC LOGIC
VVEL actuator motor relay 3   4 4 3                 DTC LOGIC
VVEL actuator shaft position sensor 3   4 4 3                 DTC LOGIC
PNP signal circuit     3   3   3 3     3     DTC LOGIC
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.