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Clearing Diagnostic Trouble Codes

  1. After performing repairs, clear Engine Control Module (ECM) memory of all stored Diagnostic Trouble Codes (DTCs) and freeze-frame data. DTCs and freeze-frame data may be cleared by using scan tool and scan tool manufacturer's instructions.
    NOTE: If using Toyota scan tool, DTCs and freeze-frame data may be cleared by switching from CHECK mode to NORMAL mode or from NORMAL mode to CHECK mode.
  2. DTCs and freeze-frame data may also be cleared by removing EFI fuse from fuse block, located in engine compartment. DTCs and freeze-frame data may also be cleared by disconnecting negative battery cable. However, other memory functions (clock, radio, alarm, seats, etc.) will be canceled and must be reset.
NOTE: Not all codes listed in the following table are used on every vehicle. See appropriate TESTS W/CODES article for a table linked to the appropriate codes for specific vehicles.
DIAGNOSTIC TROUBLE CODE (DTC) IDENTIFICATION

Code (1) Description Probable Cause
P0100 (2) Mass Airflow (MAF) Sensor Circuit Malfunction Open/Short Circuit, MAF Sensor Or ECM
P0101 (2) Mass Airflow (MAF) Circuit Range/Performance Fault MAF Sensor
P0105 Manifold Absolute Pressure (MAP) Sensor Circuit Malfunction Open/Short Circuit, MAP Sensor Or ECM
P0106 Manifold Absolute Pressure (MAP) Sensor Circuit Mal Malfunction MAP Sensor
P0110 Intake Air Temperature (IAT) Sensor Circuit Open/Short Circuit, IAT Sensor Or ECM
P0115 Engine Coolant Temperature (ECT) Sensor Circuit Fault Open/Short Circuit, ECT Sensor Or ECM
P0116 (2) ECT Sensor Circuit Range/Performance Fault ECT Sensor Or Cooling System
P0120 Throttle Position (TP) Sensor Malfunction Open/Short Circuit, TP Sensor Or ECM
P0121 (2) Throttle Position (TP) Sensor Circuit Range/Performance TP Sensor
P0125 Insufficient Coolant Temperature For Closed Loop Open/Short Circuit Or HO2S
P0130 (2) (3) Heated Oxygen Sensor Circuit Malfunction HO2S Or Fuel Trim Malfunction
P0133 (2) (3) Heated Oxygen Sensor Circuit Slow Response HO2S
P0135 (2) Heated Oxygen Sensor Heater Circuit Malfunction Open/Short In Heater Circuit, HO2S Or ECM
P0136 (2) (3) Heated Oxygen Sensor Circuit Malfunction HO2S
P0141 (2) Heated Oxygen Sensor Heater Circuit Malfunction Open/Short In Heater Circuit, HO2S Or ECM
P0150 (2) Heated Oxygen Sensor Circuit Malfunction HO2S Or Fuel Trim Malfunction
P0153 (2) Heated Oxygen Sensor Circuit Slow Response HO2S
P0155 (2) Heated Oxygen Sensor Heater Circuit Malfunction Open/Short In Heater Circuit, HO2S Or ECM
P0156 (2) Heated Oxygen Sensor Circuit Malfunction HO2S
P0161 (2) Heated Oxygen Sensor Heater Circuit Malfunction Open/Short In Heater Circuit, HO2S Or ECM
P0171 (2) Fuel Trim Malfunction Too Lean
P0172 (2) Fuel Trim Malfunction Too Rich
P0300 Random Misfire Detected Ignition, EGR, Fuel System Or Engine Mechanical
P0301 (2) Cylinder No. 1 Misfire Detected Ignition System, Fuel System Or Engine Mechanical
P0302 (2) Cylinder No. 2 Misfire Detected Ignition System, Fuel System Or Engine Mechanical
P0303 (2) Cylinder No. 3 Misfire Detected Ignition System, Fuel System Or Engine Mechanical
P0304 (2) Cylinder No. 4 Misfire Detected Ignition System, Fuel System Or Engine Mechanical
P0305 (2) Cylinder No. 5 Misfire Detected Ignition System, Fuel System Or Engine Mechanical
P0306 (2) Cylinder No. 6 Misfire Detected Ignition System, Fuel System Or Engine Mechanical
P0307 (2) Cylinder No. 7 Misfire Detected Ignition System, Fuel System Or Engine Mechanical
P0308 (2) Cylinder No. 8 Misfire Detected Ignition System, Fuel System Or Engine Mechanical
P0325 Knock Sensor No. 1 Circuit Malfunction Open/Short Circuit, Loose Sensor Or ECM
P0330 (2) Knock Sensor No. 2 Circuit Malfunction Open/Short Circuit, Loose Sensor Or ECM
P0335 (2) Crankshaft Position (CKP) Sensor Circuit Malfunction Open/Short Circuit, CKP Sensor, Starter Or ECM
P0336 (2) Crankshaft Position (CKP) Sensor Circuit Range/Performance CKP Sensor Or ECM
P0340 (2) Camshaft Position (CMP) Sensor Circuit Malfunction Open/Short Circuit, CMP Sensor Or ECM
P0401 (2) Insufficient EGR Flow Detected Open/Short EGR Circuit Or ECM
P0402 (2) Excessive EGR Flow Detected Open/Short EGR Circuit Or ECM
P0420 (2) Catalyst System Efficiency Below Threshold Catalytic Converter, Oxygen Sensor Or Circuit
P0430 (2) Catalyst System Efficiency Below Threshold Catalytic Converter, Oxygen Sensor Or Circuit
P0440 (2) EVAP System Malfunction Vapor Pressure Sensor Or Circuit, Charcoal Canister Or Faulty Vacuum Circuit
P0441 (2) Incorrect EVAP Purge Flow Open/Short Purge Control Circuit, Charcoal Canister Or Faulty Vacuum Circuit
P0446 (2) EVAP Vent Control Malfunction Open/Short VSV Circuit, Charcoal Canister Or Faulty Vacuum Circuit
P0450 EVAP Pressure Sensor Malfunction Open/Short Vapor Pressure Sensor Circuit Or ECM
P0451 EVAP Pressure Sensor Range/Performance Open/Short Vapor Pressure Sensor Circuit Or ECM
P0500 (2) Vehicle Speed Sensor Malfunction Vehicle Speed Sensor Or Circuit, Instrument Cluster Or ECM
P0505 (2) Idle Control System Malfunction IAC Valve Or Circuit Or Air Intake Hose
P0510 (2) Closed Throttle Position Switch Malfunction Closed Throttle Position Switch/Circuit Or ECM
P1100 (2) Barometric Pressure Sensor Circuit Malfunction ECM
P1120 Accelerator Pedal Position (APP) Sensor Circuit Malfunction Open/Short Circuit, APP Sensor Or ECM
P1121 Accelerator Pedal Position (APP) Sensor Range/Performance APP Sensor Or ECM
P1125 Throttle Control Motor Circuit Fault Open/Short Circuit, Throttle Control Motor Or ECM
P1126 Magnetic Clutch Circuit Fault Open/Short Circuit, Magnetic Clutch Or ECM
P1127 Electronic Throttle Control System (ETCS) Fault Open ETCS Power Circuit Or ECM
P1128 Throttle Control Motor Lock Fault Throttle Control Motor, Throttle Body Or ECM
P1129 Electronic Throttle Control System (ETCS) Fault ETCS Or ECM
P1130 (2) Air/Fuel Ratio Sensor (AFS) Circuit Range/Performance Open/Short Circuit, AFS Or ECM
P1133 (2) Air/Fuel Ratio Sensor (AFS) Response Malfunction AFS7
P1135 (2) Air/Fuel Ratio Sensor (AFS) Heater Circuit Malfunction Open/Short Circuit, AFS Or ECM
P1200 (2) Fuel Pump Relay Circuit Open/Short Relay Circuit Or ECM
P1300 Ignitor Circuit Malfunction Ignitor Circuit To ECM, Ignitor, Coil Or ECM
P1305 Ignitor Circuit Malfunction Ignitor Circuit To ECM, Ignitor, Coil Or ECM
P1310 Ignitor Circuit Malfunction Ignitor Circuit To ECM, Ignitor, Coil Or ECM
P1315 Ignitor Circuit Malfunction Ignitor Circuit To ECM, Ignitor, Coil Or ECM
P1320 Ignitor Circuit Malfunction Ignitor Circuit To ECM, Ignitor, Coil Or ECM
P1325 Ignitor Circuit Malfunction Ignitor Circuit To ECM, Ignitor, Coil Or ECM
P1330 Ignitor Circuit Malfunction Ignitor Circuit To ECM, Ignitor, Coil Or ECM
P1335 Crankshaft Position (CKP) Sensor Circuit Open/Short CKP Sensor Circuit, CKP Sensor Or ECM
P1340 Ignitor Circuit Malfunction Ignitor Circuit To ECM, Ignitor, Coil Or ECM
P1345 Variable Valve Timing (VVT) Sensor Circuit Malfunction Open/Short VVT Sensor Circuit, VVT Sensor Or ECM
P1346 Variable Valve Timing (VVT) Sensor Circuit Range/Performance Open/Short VVT Sensor Circuit, VVT Sensor Or ECM
P1349 Variable Valve Timing (VVT) System Valve Timing, Oil Control Valve, VVT Controller Or ECM
P1400 Sub-Throttle Position Sensor Malfunction Open/Short Circuit, Sub-Throttle Position Sensor Or ECM
P1401 Sub-Throttle Position Sensor Range/Performance Fault Sub-Throttle Position Sensor
P1405 Turbo Pressure Sensor Circuit Malfunction Open/Short Circuit, Turbo Pressure Sensor Or ECM
P1406 Turbo Pressure Sensor Circuit Range/Performance Fault Turbo Pressure Sensor
P1410 (2) EGR Valve Position Sensor Circuit Malfunction Open/Short Circuit, EGR Valve Position Sensor Or ECM
P1411 (2) EGR Valve Position Sensor Circuit Range/Performance EGR Valve Position Sensor
P1500 Starter Signal Circuit Malfunction Starter Signal Circuit, Ignition Switch, Starter Relay Or ECM
P1511 Boost Pressure Low Malfunction Open/Short Circuit, Air Intake Leak/Blockage, Actuator Or ECM
P1512 Boost Pressure High Malfunction Open/Short Circuit, Actuator Or ECM
P1520 (2) Stoplight Switch Signal Malfunction Short Circuit, Stoplight Switch Or ECM
P1565 Cruise Control Main Switch Circuit Malfunction Open/Short Cruise Control Switch Circuit, Cruise Control Switch Or ECM
P1600 ECM BATT Malfunction ECM Power Source Circuit Or ECM
P1605 Knock Control ECM Malfunction ECM
P1630 Traction Control System Malfunction Open/Short Circuit, Throttle Control ECU Or ECM
P1633 ECM Malfunction ECM
P1645 Body ECU Malfunction Body ECU, A/C ECU Or Communication Bus
P1652 Idle Air Control Valve Circuit Malfunction Open/Short Circuit, Wastegate Valve VSV Or ECM
P1656 Oil Control Valve Circuit Fault Open/Short Circuit, Oil Control Valve Or ECM
P1658 (2) Wastegate Valve Control Circuit Malfunction Open/Short Circuit, Wastegate Valve VSV Or ECM
P1661 (2) Exhaust Gas Control Valve Circuit Malfunction Open/Short Circuit, Exhaust Gas Control Valve VSV Or ECM
P1662 (2) Exhaust By-Pass Valve Control Circuit Malfunction Open/Short Circuit, Exhaust By-Pass Valve VSV Or ECM
P1780 (2) Park/Neutral Position Switch Malfunction Park/Neutral Position Switch/Circuit Or ECM
(1) Perform appropriate DTC test under DIAGNOSTIC TESTS in appropriate TESTS W/CODES article.
(2) Two-trip detection logic code. For more information, see TWO-TRIP DETECTION LOGIC  under INTRODUCTION.
(3) Some models are equipped with non-heated oxygen sensors.
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