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DTC B1781: Front Occupant Classification Sensor RH Circuit Malfunction [08/2019 - ]: Description

The front occupant detection sensor RH circuit consists of the occupant classification ECU and the front occupant detection sensor RH.

DTC B1781 is stored when a malfunction is detected in the front occupant detection sensor RH circuit.

DTC Code	DTC Detection Condition	Trouble Area
B1781	One of following conditions is met: Occupant classification ECU receives line short circuit signal, open circuit signal, short circuit to ground signal or short circuit to +B signal in front occupant detection sensor RH circuit for 2 seconds Front occupant detection sensor RH malfunction Occupant classification ECU malfunction	Front seat with adjuster frame assembly RH (Front occupant detection sensor RH) Front seat wire RH Occupant classification ECU

HINT:

When DTC B1650 is detected as a result of troubleshooting the airbag system, perform troubleshooting for DTC B1781 of the occupant classification system.
Use the Techstream to check for DTCs of the occupant classification ECU, otherwise the DTC cannot be read.