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.
2013 Lexus IS 350C BaseFACTORY OEM SERVICE PROCEDURE
Occupant Classification System
OCCUPANT CLASSIFICATION SYSTEM DIAGNOSTIC TROUBLE CODE (DTC) IDENTIFICATION
| DTC Code | Description |
|---|---|
| B1771 | Passenger Side Buckle Switch Circuit Malfunction |
| B1773 | Belt Tension Sensor Circuit Malfunction |
| B1774 | Pressure Sensor Circuit Malfunction |
| B1775 | Pressure Sensor Power Source Circuit Malfunction |
| B1776 | Seat Belt Tension Sensor Power Source Circuit Malfunction |
| B1790 | Center Airbag Sensor Assembly Communication Circuit Malfunction |
| B1795 | Occupant Classification ECU Malfunction |
| B1797 | Calibration 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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