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Clearing Diagnostic Trouble Codes

  1. After performing repairs, clear ECM memory of all stored Diagnostic Trouble Codes (DTCs) and freeze-frame data. DTCs and freeze-frame data may be cleared by using scan tester and scan tester manufacturer's instructions.
    NOTE: If using Toyota scan tester, 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 cancelled and must be reset.
NOTE: Not all codes listed in the following table are used on every vehicle.
TROUBLE CODE IDENTIFICATION

Code (1) Component/System Most Likely Cause
P0100  Mass Airflow (MAF) Sensor Circuit Open/Short Circuit, MAF Sensor Or ECM
P0101 (2) Mass Airflow (MAF) Sensor Circuit Range/Performance Problem MAF Sensor
P0110  Intake Air Temperature (IAT) Sensor Circuit Open/Short Circuit, IAT Sensor Or ECM
P0115  Engine Coolant Temperature (ECT) Sensor Circuit Open/Short Circuit, ECT Sensor Or ECM
P0116 (2) Engine Coolant Temperature (ECT) Sensor Circuit ECT Sensor Or Cooling System
P0120  Throttle Position (TP) Sensor Open/Short Circuit, TP Sensor Or ECM
P0121 (2) Throttle Position (TP) Sensor TP Sensor
P0125  Insufficient Coolant Temperature For Closed Loop Open/Short Circuit Or HO2S
P0130 (2) (3) Heated Oxygen Sensor Circuit (Sensor No. 1) HO2S Or Fuel Trim Malfunction
P0133 (2) (3) Heated Oxygen Sensor Circuit (Sensor No. 1) Slow Response HO2S
P0135 (2) Heated Oxygen Sensor Heater Circuit (Sensor No. 1) Open/Short In Heater Circuit, HO2S Or ECM
P0136 (2) (3) Heated Oxygen Sensor Circuit (Sensor No. 2) HO2S
P0141 (2) (3) Heated Oxygen Sensor Heater Circuit (Sensor No. 2) 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
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 "A" Circuit Open/Short Circuit, CKP Sensor, Starter Or ECM
P0340 (2) Camshaft Position (CMP) Sensor Circuit Open/Short Circuit, CMP Sensor Or ECM
P0385 (2) Camshaft Position (CMP) Sensor "B" Circuit Open/Short Circuit, CMP Sensor Or ECM
P0401 (2) Insufficient Exhaust Gas Recirculation (EGR) Flow Detected Open/Short EGR Circuit Or ECM
P0402 (2) Excessive Exhaust Gas Recirculation (EGR) Flow Detected Open/Short EGR Circuit Or ECM
P0420 (2) Catalyst System Efficiency Below Threshold Catalytic Converter, Oxygen Sensor Or Circuit
P0500 (2) Vehicle Speed Sensor Malfunction Vehicle Speed Sensor Or Circuit, Instrument Cluster Or ECM
P0505 (2) Idle Air Control (IAC) System Malfunction IAC Valve Or Circuit Or Air Intake Hose
P0510 (2) Closed Throttle Position (CTP) Switch Malfunction Closed Throttle Position Switch/Circuit Or ECM
P1300  Ignitor Circuit Malfunction Ignitor Circuit To ECM, Ignitor Or ECM
P1335  Crankshaft Position (CKP) Sensor Circuit (Engine Running) Open/Short CKP Sensor Circuit Or ECM
P1500  Starter Signal Circuit Malfunction Starter Signal Circuit, Ignition Switch, Starter Relay Or ECM
P1600  ECM BATT Malfunction ECM Power Source Circuit Or ECM
P1605  Knock Control CPU Malfunction ECM
P1780 (2) Park/Neutral Position Switch Malfunction Park/Neutral Position Switch/Circuit Or ECM
(1) Perform appropriate circuit test.
(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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