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.
2012 Toyota Sienna SEFACTORY OEM SERVICE PROCEDURE
Lighting System
LIGHTING SYSTEM DIAGNOSTIC TROUBLE CODE (DTC) IDENTIFICATION
| DTC Code | Description |
|---|---|
| B1244 | Light Sensor Circuit Malfunction |
| B124A | Automatic High Beam Mirror |
| B124B | Automatic High Beam System |
| B124C | Automatic High Beam Camera |
| B2414 | Steering Position Sensor Malfunction |
| B2415 | Vehicle Speed Sensor Malfunction |
| U0101 | Lost Communication with ECM |
| U0126 | Lost Communication with Steering Angle Sensor Module |
| U0129 | Lost Communication with Skid Control ECU |
| U0142 | Lost Communication with Main Body ECU |
| U0182 | Lost Communication with AFS ECU |
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.