LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Lexus >> 2012 >> LS 600hL >> Repair and Diagnosis >> External Pages >> Different car >> Section 27 (Occupant Classification System (Diagnostics - Introduction)) >> Occupant Classification System >> Diagnostic Trouble Code Chart >> Diagnostic Trouble Code Chart
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Diagnostic Trouble Code Chart

WARNING: This page is about a different car, the 2012 Lexus CT 200h. However, it is still accessible from the selected car via links, so may be relevant.

If a trouble code is displayed during the DTC check, check the circuit listed for the code in the table below (proceed to "See" listed for that circuit).

HINT: 

When DTC B1650/32 is detected as a result of troubleshooting for the airbag system, perform troubleshooting for the occupant classification system as shown in the chart below.

OCCUPANT CLASSIFICATION SYSTEM

DTC Code Detection Item Trouble Area Passenger Airbag ON/OFF Indicator (OFF indicator) See
B1771 Passenger Side Buckle Switch Circuit Malfunction 1. Front seat wire RH
2. Front seat inner belt assembly RH (Passenger side buckle switch)
3. Occupant detection ECU
ON Refer to DTC B1771: Passenger Side Buckle Switch Circuit Malfunction
B1780 Front Occupant Classification Sensor LH Circuit Malfunction 1. Front seat wire RH
2. Front seat cushion spring assembly (Front occupant classification sensor LH)
ON Refer to DTC B1780: Front Occupant Classification Sensor LH Circuit Malfunction
B1781 Front Occupant Classification Sensor RH Circuit Malfunction 1. Front seat wire RH
2. Front seat cushion spring assembly (Front occupant classification sensor RH)
ON Refer to DTC B1781: Front Occupant Classification Sensor RH Circuit Malfunction
B1782 Rear Occupant Classification Sensor LH Circuit Malfunction 1. Front seat wire RH
2. Front seat cushion spring assembly (Rear occupant classification sensor LH)
ON Refer to DTC B1782: Rear Occupant Classification Sensor LH Circuit Malfunction
B1783 Rear Occupant Classification Sensor RH Circuit Malfunction 1. Front seat wire RH
2. Front seat cushion spring assembly (Rear occupant classification sensor RH)
ON Refer to DTC B1783: Rear Occupant Classification Sensor RH Circuit Malfunction
B1785 Front Occupant Classification Sensor LH Collision Detection Front seat cushion spring assembly (Front occupant classification sensor LH) ON Refer to DTC B1785: Front Occupant Classification Sensor LH Collision Detection
B1786 Front Occupant Classification Sensor RH Collision Detection Front seat cushion spring assembly (Front occupant classification sensor RH) ON Refer to DTC B1786: Front Occupant Classification Sensor RH Collision Detection
B1787 Rear Occupant Classification Sensor LH Collision Detection Front seat cushion spring assembly (Rear occupant classification sensor LH) ON Refer to DTC B1787: Rear Occupant Classification Sensor LH Collision Detection
B1788 Rear Occupant Classification Sensor RH Collision Detection Front seat cushion spring assembly (Rear occupant classification sensor RH) ON Refer to DTC B1788: Rear Occupant Classification Sensor RH Collision Detection
B1790 Center Airbag Sensor Assembly Communication Circuit Malfunction 1. No. 2 floor wire
2. Front seat wire RH
3. Occupant detection ECU
4. Airbag sensor assembly
ON Refer to DTC B1790: Center Airbag Sensor Assembly Communication Circuit Malfunction
B1793 Occupant Classification Sensor Power Supply Circuit Malfunction 1. Front seat wire RH
2. Front seat cushion spring assembly (4 occupant classification sensors)
ON Refer to DTC B1793: Occupant Classification Sensor Power Supply Circuit Malfunction
B1794 Open in Occupant Classification ECU Battery Positive Line 1. Auxiliary battery
2. ECU-B fuse
3. Wire harness
4. Occupant detection ECU
ON Refer to DTC B1794: Open in Occupant Classification ECU Battery Positive Line
B1795 Occupant Classification ECU Malfunction Occupant detection ECU ON Refer to DTC B1795: Occupant Classification ECU Malfunction
B1796 Sleep Operation Failure of Occupant Classification ECU Occupant detection ECU ON Refer to DTC B1796: Sleep Operation Failure of Occupant Classification ECU