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Home >> Toyota >> 2012 >> Matrix Base, Automatic Trans >> Repair and Diagnosis >> External Pages >> Different car >> Section 362 (Occupant Classification System (Diagnostic Codes & Symptom Tests)) >> Occupant Classification System >> DTC B1773: Belt Tension Sensor Circuit Malfunction; DTC B1776: Seat Belt Tension Sensor Power Source Circuit Malfunction >> Description
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DTC B1773: Belt Tension Sensor Circuit Malfunction; DTC B1776: Seat Belt Tension Sensor Power Source Circuit Malfunction: Description

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

The seat belt tension sensor circuit consists of the occupant classification ECU and the seat belt tension sensor.

The seat belt tension sensor sends the seat belt tension signal to the occupant classification ECU.

DTC B1773 and B1776 are recorded when a malfunction is detected in the seat belt tension sensor circuit.

DTC No. DTC Detecting Condition Trouble Area
B1773
B1776
  • The occupant classification ECU receives a short circuit signal, open circuit signal and short circuit to ground signal or a short circuit to B+ signal in the seat belt tension sensor circuit for 2 seconds.
  • Seat belt tension sensor malfunction
  • Occupant classification ECU malfunction
  • No. 2 floor wire
  • Front seat wire RH
  • Front seat outer belt assembly RH (Seat belt tension sensor)
  • Occupant classification ECU

HINT: 

When DTC B1650/32 is detected as a result of troubleshooting for the airbag system, check the DTCs stored in the occupant classification ECU. When DTC B1773 and B1776 are output, perform troubleshooting for those DTCs.