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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 Lexus 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 junction 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.
DIAGNOSTIC TROUBLE CODE (DTC) IDENTIFICATION

DTC System Affected Possible Cause
P0100  Mass Airflow (MAF) Sensor Circuit Open/Short Circuit, MAF Sensor Or ECM
P0101 (1) MAF 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 Open/Short Circuit, ECT Sensor Or ECM
P0116 (1) Engine Coolant Temperature (ECT) Sensor ECT Sensor Or Cooling System
P0120  Throttle Position (TP) Sensor Open/Short Circuit, TP Sensor Or ECM
P0121 (1) Throttle Position (TP) Sensor TP Sensor
P0125  Insufficient Coolant Temperature For Closed Loop Open/Short Circuit Or HO2S
P0130 (1) (2) Heated Oxygen Sensor Circuit (Bank 1, Sensor 1) HO2S Or Fuel Trim Malfunction
P0133 (1) (2) Heated Oxygen Sensor Circuit Slow Response (Bank 1, Sensor 1) HO2S
P0135 (1) (2) Heated Oxygen Sensor Heater Circuit (Bank 1, Sensor 1) Open/Short In Heater Circuit, HO2S Or ECM
P0136 (1) (2) Heated Oxygen Sensor Circuit (Bank 1, Sensor 2) HO2S
P0141 (1) (2) Heated Oxygen Sensor Heater Circuit (Bank 1, Sensor 2) Open/Short In Heater Circuit, HO2S Or ECM
P0150 (1) (2) Heated Oxygen Sensor Circuit (Bank 2, Sensor 1) HO2S Or Fuel Trim Malfunction
P0153 (1) (2) Heated Oxygen Sensor Circuit Slow Response (Bank 2, Sensor 1) HO2S
P0155 (1) (2) Heated Oxygen Sensor Heater Circuit (Bank 2, Sensor 1) Open/Short In Heater Circuit, HO2S Or ECM
P0156 (1) (2) Heated Oxygen Sensor Heater Circuit (Bank 2, Sensor 2) HO2S
P0161 (1) (2) Heated Oxygen Sensor Heater Circuit (Bank 2, Sensor 2) Open/Short In Heater Circuit, HO2S Or ECM
P0171 (1) Fuel Trim Malfunction Too Lean
P0172 (1) Fuel Trim Malfunction Too Rich
P0300  Random Misfire Detected Ignition, EGR, Fuel System Or Engine Mechanical
P0301 (1) Cylinder No. 1 Misfire Detected Ignition System, Fuel System Or Engine Mechanical
P0302 (1) Cylinder No. 2 Misfire Detected Ignition System, Fuel System Or Engine Mechanical
P0303 (1) Cylinder No. 3 Misfire Detected Ignition System, Fuel System Or Engine Mechanical
P0304 (1) Cylinder No. 4 Misfire Detected Ignition System, Fuel System Or Engine Mechanical
P0305 (1) Cylinder No. 5 Misfire Detected Ignition System, Fuel System Or Engine Mechanical
P0306 (1) Cylinder No. 6 Misfire Detected Ignition System, Fuel System Or Engine Mechanical
P0307 (1) Cylinder No. 7 Misfire Detected Ignition System, Fuel System Or Engine Mechanical
P0308 (1) Cylinder No. 8 Misfire Detected Ignition System, Fuel System Or Engine Mechanical
P0325  Knock Sensor No. 1 (Right Bank) Circuit Malfunction Open/Short Circuit, Loose Sensor Or ECM
P0330 (1) Knock Sensor No. 2 (Left Bank) Circuit Malfunction Open/Short Circuit, Loose Sensor Or ECM
P0335 (1) Crankshaft Position (CKP) Sensor Circuit Open/Short Circuit, CKP Sensor, Starter Or ECM
P0340 (1) Camshaft Position (CMP) Sensor Circuit Open/Short Circuit, CMP Sensor Or ECM
P0401 (1) Insufficient EGR Flow Detected Open/Short EGR Circuit Or ECM
P0402 (1) Excessive EGR Flow Detected Open/Short EGR Circuit Or ECM
P0403 (1) EGR Circuit Malfunction Open/Short EGR Circuit Or ECM
P0420 (1) Catalyst System Efficiency Below Threshold Catalytic Converter, Oxygen Sensor Or Circuit
P0430 (1) Catalyst System Efficiency Below Threshold (Bank 2) Catalytic Converter, Oxygen Sensor Or Circuit
P0441 (1) Incorrect EVAP Purge Flow Open/Short Purge Control Circuit, Charcoal Canister Or Faulty Vacuum Circuit
P0500 (1) Vehicle Speed Sensor Malfunction Vehicle Speed Sensor Or Circuit, Instrument Cluster Or ECM
P0505 (1) Idle Control System Malfunction IAC Valve Or Circuit, A/C Idle-Up VSV Or Air Intake Hose
P0510 (1) Closed Throttle Position Switch Malfunction Closed Throttle Position Switch/Circuit Or ECM
P1100  Barometric Pressure Sensor Circuit ECM
P1200 (1) Fuel Pump Relay Circuit Open/Short Relay Circuit Or ECM
P1300  Ignitor Circuit Malfunction Ignitor Circuit To ECM, Ignitor Or ECM
P1305  Ignitor Circuit Malfunction (Bank 2) Ignitor Circuit To ECM, Ignitor Or ECM
P1335  Crankshaft Position (CKP) Sensor Circuit (Engine Running) Open/Short CKP Sensor Circuit Or ECM
P1400  Sub-Throttle Position Sensor Circuit Open/Short Sub-Throttle Position Sensor Circuit Or ECM
P1401 (1) Sub-Throttle Position Sensor Malfunction Sub-Throttle Position Sensor
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 ECM Malfunction ECM
P1780 (1) Park/Neutral Position Switch Malfunction Park/Neutral Position Switch/Circuit Or ECM
(1) Two-trip detection logic code. For more information, see TWO-TRIP DETECTION LOGIC  under INTRODUCTION.
(2) Bank 1 refers to bank that includes cylinder No. 1. Bank 2 refers to bank without cylinder No. 2. Sensor 1 refers to sensor closest to engine block.
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