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.
1999 Toyota Sienna LEFACTORY OEM SERVICE PROCEDURE
Diagnostic Trouble Code Definitions
DIAGNOSTIC TROUBLE CODE (DTC) IDENTIFICATION
| DTC (1) | Description | ||||||
|---|---|---|---|---|---|---|---|
| B2795 (2) | Unmatched Key Code | ||||||
| B2796 (2) | No Communication In Immobilizer System | ||||||
| B2797 (2) | Communication Malfunction No. 1 | ||||||
| B2798 (2) | Communication Malfunction No. 2 | ||||||
| dtc P0100 | Mass Airflow (MAF) Meter Circuit | ||||||
| dtc P0101 | Mass Airflow (MAF) Meter Circuit Range/Performance | ||||||
| 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 | ||||||
| dtc P0120 | Throttle Position (TP) Sensor Circuit | ||||||
| dtc P0121 | Throttle Position (TP) Sensor Circuit Range/Performance | ||||||
| dtc P0125 | Insufficient Coolant Temperature For Closed Loop Fuel Control (Except Calif. Emissions) | ||||||
| dtc P0125 | Insufficient Coolant Temperature For Closed Loop Fuel Control (Calif. Emissions) | ||||||
| dtc P0130 | Heated Oxygen Sensor No. 1 Circuit (Except Calif. Emissions) | ||||||
| dtc P0133 | Heated Oxygen Sensor No. 1 Circuit Slow Response (Except Calif. Emissions) | ||||||
| dtc P0135 | Heated Oxygen Sensor No. 1 Heater Circuit (Except Calif. Emissions) | ||||||
| dtc P0136 | Heated Oxygen Sensor No. 2 Circuit | ||||||
| dtc P0141 | Heated Oxygen Sensor No. 2 Heater Circuit | ||||||
| dtc P0150 | Heated Oxygen Sensor No. 1 Circuit (Except Calif. Emissions) | ||||||
| dtc P0153 | Heated Oxygen Sensor No. 1 Circuit Slow Response (Except Calif. Emissions) | ||||||
| dtc P0155 | Heated Oxygen Sensor No. 1 Heater Circuit (Except Calif. Emissions) | ||||||
| dtc P0171 | System Too Lean (Except Calif. Emissions) | ||||||
| dtc P0171 | System Too Lean (Calif. Emissions) | ||||||
| dtc P0172 | System Too Rich (Except Calif. Emissions) | ||||||
| dtc P0172 | System Too Rich (Calif. Emissions) | ||||||
| dtc P0300 | Random Misfire Detected | ||||||
| dtc P0301 | Cylinder No. 1 Misfire Detected | ||||||
| dtc P0302 | Cylinder No. 2 Misfire Detected | ||||||
| dtc P0303 | Cylinder No. 3 Misfire Detected | ||||||
| dtc P0304 | Cylinder No. 4 Misfire Detected | ||||||
| dtc P0305 | Cylinder No. 5 Misfire Detected | ||||||
| dtc P0306 | Cylinder No. 6 Misfire Detected | ||||||
| dtc P0325 | Knock Sensor No. 1 Circuit | ||||||
| dtc P0330 | Knock Sensor No. 2 Circuit | ||||||
| dtc P0335 | Crankshaft Position (CKP) Sensor Circuit | ||||||
| dtc P0340 | Camshaft Position (CMP) Sensor Circuit | ||||||
| dtc P0420 | Catalyst System Efficiency Below Threshold (Except Calif. Emissions) | ||||||
| dtc P0420 | Catalyst System Efficiency Below Threshold (Calif. Emissions) | ||||||
| dtc P0440 | Evaporative Emission Control System (EVAP) | ||||||
| dtc P0441 | Incorrect EVAP Purge Flow | ||||||
| dtc P0446 | EVAP Vent Control Circuit | ||||||
| dtc P0450 | EVAP Pressure Sensor Circuit | ||||||
| dtc P0451 | EVAP Pressure Sensor Range/Performance | ||||||
| dtc P0500 | Vehicle Speed Sensor Circuit | ||||||
| dtc P0505 | Idle Air Control (IAC) System Circuit | ||||||
| P0710 (3) | Transmission Fluid Temperature Sensor Malfunction | ||||||
| P0750 (3) | Shift Solenoid Valve No. 1 Malfunction | ||||||
| P0753 (3) | Shift Solenoid Valve No. 1 Electrical Malfunction | ||||||
| P0755 (3) | Shift Solenoid Valve No. 2 Malfunction | ||||||
| P0758 (3) | Shift Solenoid Valve No. 2 Electrical Malfunction | ||||||
| P0770 (3) | Lock-Up Solenoid Malfunction | ||||||
| P0773 (3) | Lock-Up Solenoid Circuit Electrical Malfunction | ||||||
| dtc P1130 | Air/Fuel Sensor Circuit Range/Performance (Calif. Emissions) | ||||||
| dtc P1133 | Air/Fuel Sensor Circuit Response (Calif. Emissions) | ||||||
| dtc P1135 | Air/Fuel Sensor Heater Circuit (Calif. Emissions) | ||||||
| dtc P1150 | Air/Fuel Sensor Circuit Range/Performance (Calif. Emissions) | ||||||
| dtc P1153 | Air/Fuel Sensor Circuit Response (Calif. Emissions) | ||||||
| dtc P1155 | Air/Fuel Sensor Heater Circuit (Calif. Emissions) | ||||||
| dtc P1300 | Ignitor Circuit | ||||||
| dtc P1335 | Crankshaft Position (CKP) Sensor Circuit | ||||||
| dtc P1520 | Stoplight Switch Signal Circuit (A/T Only) | ||||||
| dtc P1600 | ECM BATT Circuit | ||||||
| dtc P1780 | Park/Neutral Position (PNP) Switch Circuit | ||||||
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Factory Service Tools
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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.