DTC B1780: Front Occupant Classification Sensor LH Circuit Malfunction [08/2016 - ]: Description

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

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

DTC No.	Detection Item	DTC Detection Condition	Trouble Area
B1780	Front Occupant Classification Sensor LH Circuit Malfunction	The occupant detection ECU detects a line short, short to ground or B+, or an open in the front occupant classification sensor LH circuit. Front occupant classification sensor LH malfunction Occupant detection ECU malfunction	for TMMMS Made: Front seat wire RH Front occupant classification sensor LH (Separate type front seat cushion spring assembly RH)* Occupant detection ECU for TMMC Made: Front seat wire RH Front seat inner belt assembly RH Front occupant classification sensor LH (Front seat adjuster sub-assembly RH)* Occupant detection ECU

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

B1780

Front Occupant Classification Sensor LH Circuit Malfunction

The occupant detection ECU detects a line short, short to ground or B+, or an open in the front occupant classification sensor LH circuit.
Front occupant classification sensor LH malfunction
Occupant detection ECU malfunction

for TMMMS Made:

Front seat wire RH
Front occupant classification sensor LH (Separate type front seat cushion spring assembly RH)*
Occupant detection ECU

for TMMC Made:

Front seat wire RH
Front seat inner belt assembly RH
Front occupant classification sensor LH (Front seat adjuster sub-assembly RH)*
Occupant detection ECU

*: The front occupant classification sensor LH is built into the separate type front seat cushion spring assembly RH or front seat adjuster sub-assembly RH.