ENGINE CONTROL SYSTEM TESTS W/CODES - 4-Cylinder

• Diagnostic Trouble Code Definitions
• Self-Diagnostic Tests
  • * Please Read First *
  • DTC P0100: Mass Airflow (MAF) Sensor Circuit
    • Notes
    • Circuit Description
    • Diagnosis & Repair
  • DTC P0101: Mass Airflow (MAF) Sensor Circuit Range/Performance Problem
    • Condition
    • Diagnosis & Repair Procedure
  • DTC P0110: Intake Air Temperature (IAT) Sensor Circuit
    • Notes
    • Circuit Description
    • Diagnosis & Repair
  • DTC P0115: Engine Coolant Temperature (ECT) Sensor Circuit
    • Notes
    • Circuit Description
    • Diagnosis & Repair
  • DTC P0116: Engine Coolant Temperature (ECT) Sensor Circuit Range/Performance Problem
    • Condition
    • Diagnosis & Repair
  • DTC P0120: Throttle Position (TP) Sensor/Switch Circuit Malfunction
    • Notes
    • Circuit Description
    • Diagnosis & Repair
  • DTC P0121: Throttle Position (TP) Sensor/Switch Circuit Range/Performance Problem
    • Condition
    • Diagnosis & Repair
  • DTC P0125: Insufficient Coolant Temperature For Closed Loop Fuel Control
    • Notes
    • Circuit Description
    • Diagnosis & Repair
  • DTC P0130: Heated Oxygen Sensor Circuit (Sensor No. 1)
    • Notes
    • Condition
    • Test Drive Confirmation
    • Diagnosis & Repair Procedure
  • DTC P0133: Heated Oxygen Sensor Circuit (Sensor No. 1) Slow Response
    • Notes
    • Condition
    • Diagnosis & Repair
  • DTC P0135 Or P0141: Heated Oxygen Sensor Circuit Fault
    • Notes
    • Condition
    • Diagnosis & Repair
  • DTC P0136: Heated Oxygen Sensor Circuit (Sensor No. 2)
    • Notes
    • Condition
    • Diagnosis & Repair
  • DTC P0141: Heated Oxygen Sensor Circuit (Sensor No. 2)
  • DTC P0171: System Too Lean (Fuel Trim) DTC P0172: System Too Rich (Fuel Trim)
    • Notes
    • Circuit Description
    • Diagnosis & Repair
  • DTC P0300: Random Misfire Detected
    • Circuit Description
    • Test Drive Confirmation
    • Diagnosis & Repair
  • DTCS P0301-P0304: Cylinders No. 1-4 Misfire Detected
    • Notes
    • Circuit Description
    • Condition
    • Diagnosis & Repair
  • DTC P0325: Knock Sensor Circuit
    • Notes
    • Circuit Description
    • Diagnosis & Repair
  • DTC P0335 Or P1335: Crankshaft Position (CKP) Sensor Circuit
    • Notes
    • Circuit Description
    • Diagnosis & Repair
  • DTC P0340: Camshaft Position (CMP) Sensor Circuit
    • Notes
    • Circuit Description
    • Diagnosis & Repair
  • DTC P0401: Insufficient Exhaust Gas RECIRCULATION (EGR) Flow Detected
    • Notes
    • Circuit Description
    • Test Drive Confirmation
    • Diagnosis & Repair (Using Toyota Scan Tool)
    • Diagnosis & Repair (Using OBD-II Scan Tool)
  • DTC P0402: Excessive Exhaust Gas RECIRCULATION (EGR) Flow Detected
    • Notes
    • Circuit Description
    • Test Drive Confirmation
    • Diagnosis & Repair (Using Toyota Scan Tool
    • Diagnosis & Repair (Using OBD-II Scan Tool)
  • DTC P0420: Catalyst System Efficiency Below Threshold
    • Notes
    • Circuit Description
    • Diagnosis & Repair
  • DTC P0440: Evaporative Emission Control System Malfunction
    • Notes
    • Circuit Description
    • Diagnosis & Repair
  • DTC P0441: Evaporative Emission Control System, Incorrect Purge Flow Or DTC P0446: EVAP Vent Control Malfunction
    • Notes
    • Circuit Description
    • Diagnosis & Repair (Using Toyota Scan Tool)
    • Diagnosis & Repair (Using OBD-II Scan Tool)
  • DTC P0450: EVAP Pressure Sensor Fault Or DTC P0451: EVAP Pressure Sensor Range/Performance
    • Notes
    • Circuit Description
    • Diagnosis & Repair
  • DTC P0500: Vehicle Speed Sensor Fault
    • Notes
    • Circuit Description
    • Diagnosis & Repair
  • DTC P0505: Idle Air Control (IAC) System Malfunction
    • Notes
    • Circuit Description
    • Repair & Diagnosis
  • DTC P1300: IGNITOR Circuit No. 1 Fault
    • Notes
    • Circuit Description
    • Diagnosis & Repair
  • DTC P1310: IGNITOR Circuit No. 2 Fault
    • Notes
    • Circuit Description
    • Diagnosis & Repair
  • DTC P1335: Crankshaft Position (CKP) Sensor Circuit
  • DTC P1520: Stoplight Switch Signal Malfunction (A/T Only)
    • Notes
    • Circuit Description
    • Diagnosis & Repair
  • DTC P1600: ECM Batt Malfunction
    • Notes
    • Circuit Description
    • Diagnosis & Repair
  • DTC P1780: Park/Neutral Position (PNP) Switch (A/T Only)
    • Notes
    • Circuit Description
    • Diagnosis & Repair