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.
2001 Lexus RX 300 AWDFACTORY OEM SERVICE PROCEDURE
Engine Performance DTCS
ENGINE PERFORMANCE DIAGNOSTIC TROUBLE CODE (DTC) IDENTIFICATION
| DTC | Description |
|---|---|
| P0100 | Mass Airflow (MAF) Sensor Circuit |
| P0101 | Mass Airflow (MAF) Sensor Circuit Range/Performance Fault |
| P0110 | Intake Air Temperature (IAT) Sensor Circuit |
| P0115 | Engine Coolant Temperature (ECT) Sensor Circuit |
| P0116 | Engine Coolant Temperature (ECT) Circuit Range/Performance Fault |
| P0120 | Throttle (TP)/Pedal Position Sensor Switch "A" Circuit Malfunction |
| P0121 | Throttle (TP)/Pedal Position Sensor Switch "A" Circuit Range/Performance Fault |
| P0125 | Insufficient Coolant Temperature For Closed Loop Fuel Control |
| P0128 | Thermostat Malfunction |
| P0136 | Heated Oxygen Sensor Circuit Fault (Bank 1 Sensor 2) |
| P0141 | Heated Oxygen Sensor Heater Circuit Fault (Bank 1 Sensor 2) |
| P0171 | System Too Lean (Fuel Trim - Bank 1) |
| P0172 | System Too Rich (Fuel Trim - Bank 1) |
| P0174 | System Too Lean (Fuel Trim - Bank 2) |
| P0175 | System Too Rich (Fuel Trim - Bank 2) |
| P0300 | Random Cylinder Misfire Detected |
| P0301-P0306 | Cylinders No. 1-6 Misfire Detected |
| P0325/P0330 | Knock Sensor Circuit Fault |
| P0335 | Crankshaft Position (CKP) Sensor Circuit |
| P0340 | Variable Valve Timing (VVT) Sensor Circuit |
| P0420 | Catalyst System Efficiency Below Threshold |
| P0440 | EVAP System Malfunction |
| P0441 | Incorrect EVAP Purge Flow |
| P0442 | EVAP System Small Leak Detected |
| P0446 | EVAP Vent Control Fault |
| P0450 | EVAP Pressure Sensor Malfunction |
| P0451 | EVAP Pressure Sensor Range/Performance Fault |
| P0500 | Vehicle Speed Sensor (VSS) Malfunction |
| P0505 | Idle Control System Malfunction |
| P1130/P1150 | Air/Fuel Sensor Circuit Range/Performance Fault |
| P1133/P1153 | Air/Fuel Sensor Circuit Response Malfunction |
| P1135/P1155 | Air/Fuel Sensor Heater Circuit Malfunction |
| P1300, P1305, P1310, P1315, P1320 Or P1325 | Ignitor Circuit Malfunction |
| P1335 | Crankshaft Position (CKP) Sensor Circuit |
| P1346/P1351 | Variable Valve Timing (VVT) Circuit Range/Performance Fault |
| P1349/P1354 | Variable Valve Timing (VVT) System Malfunction |
| P1350 | Variable Valve Timing (VVT) Circuit Malfunction |
| P1520 | Stoplight Switch Signal Malfunction |
| P1600 | ECM Batt Malfunction |
| P1656/P1663 | Oil Control Valve (OCV) Malfunction |
| P1780 | Park/Neutral Position Switch 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.
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