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DTC B1780: Front Occupant Classification Sensor LH Circuit Malfunction [08/2019 - ]: Description

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

DTC B1780 is stored when a malfunction is detected in the front occupant detection sensor LH circuit.

DTC Code	DTC Detection Condition	Trouble Area
B1780	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 LH circuit for 2 seconds Front occupant detection sensor LH malfunction Occupant classification ECU malfunction	Front seat with adjuster frame assembly RH (Front occupant detection sensor LH) 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 B1780 of the occupant classification system.
Use the Techstream to check for DTCs of the occupant classification ECU, otherwise the DTC cannot be read.