Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
2002 Lexus IS 300 Base, AutomaticFACTORY OEM SERVICE PROCEDURE
Engine Controls - Self-Diagnostics
- Introduction
- Self-Diagnostic System
- Scan Tool Problems
- Summary
- Diagnostic Tests
- Notes
- DTC P0100: Mass Airflow (MAF) Sensor Circuit
- DTC P0101: Mass Airflow (MAF) Sensor Circuit Range/Performance Fault
- DTC P0110: Intake Air Temperature (IAT) Sensor Circuit
- DTC P0115: Engine Coolant Temperature (ECT) Sensor Circuit
- DTC P0116: Engine Coolant Temperature (ECT) Sensor Circuit Range/Performance Fault
- DTC P0120: Throttle Position (TP) Sensor Circuit Malfunction
- DTC P0121: Throttle Position (TP) Sensor Circuit Range/Performance Fault
- DTC P0125: Insufficient Coolant Temperature For Closed Loop Fuel Control
- DTC P0128: Thermostat Fault
- DTC P0130 Or DTC P0150: Heated Oxygen Sensor Circuit Malfunction
- DTC P0133 Or DTC P0153: Heated Oxygen Sensor Circuit Slow Response
- DTC P0135, DTC P0141, DTC P0155 Or DTC P0161
- DTC P0136 Or DTC P0156: Heated Oxygen Sensor Circuit Malfunction
- DTC P0171, DTC P0172, DTC P0174 Or DTC P0175
- DTC P0300: Random Cylinder Misfire Detected
- DTC P0301, DTC P0302, DTC P0303, DTC P0304, DTC P0305 Or DTC P0306
- DTC P0325 Or DTC P0330: Knock Sensor Circuit Malfunction
- DTC P0335 Or DTC P1335
- DTC P0340: Camshaft Position (CMP) Sensor Circuit
- DTC P0420 Or DTC P0430: Catalyst System
- DTC P0440: EVAP System Malfunction
- DTC P0441 Or DTC P0446
- DTC P0450 Or DTC P0451
- DTC P0500: Vehicle Speed Sensor (VSS) Malfunction
- DTC P0505: Idle Control System Malfunction
- DTC P0550: Power Steering Pressure Sensor Circuit Malfunction
- DTC P1120: Accelerator Pedal Position Sensor Circuit Malfunction
- DTC P1121: Accelerator Position Sensor Circuit Malfunction
- DTC P1125: Throttle Control Motor Circuit Malfunction
- DTC P1126: Electromagnetic Clutch Circuit Malfunction
- DTC P1127: Electronic Throttle Control System (ETCS) Actuator Power Source Circuit Malfunction
- DTC P1128: Throttle Control Motor Lock Malfunction
- DTC P1129: Electronic Throttle Control System (ETCS) Malfunction
- DTC P1200: Fuel Pump Relay Circuit Malfunction
- DTC P1300: IGNITOR Circuit Malfunction
- DTC P1335: Crankshaft Position Sensor Circuit Malfunction (During Engine Running)
- DTC P1346: Variable Valve Timing (VVT) Circuit Range/Performance Fault
- DTC P1349: Variable Valve Timing (VVT) System Malfunction
- DTC P1520: Stoplight Switch Signal Malfunction
- DTC P1600: ECM Batt Malfunction
- DTC P1633: Electronic Throttle Control System (ETCS) Circuit ECM Malfunction
- DTC P1645: Body Ecu Malfunction
- DTC P1656: Oil Control Valve (OCV) Circuit Malfunction
Factory Service Tools
Use the Manual With the Right Hardware
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.