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DTC B1771: Passenger Side Buckle Switch Circuit Malfunction [08/2015 - 08/2019]: Description

The passenger side buckle switch circuit consists of the occupant classification ECU and front seat inner belt RH.

DTC B1771 is stored when a malfunction is detected in the passenger side buckle switch circuit.

Troubleshoot DTC B1771 first when DTCs B1771 and B1795 are output simultaneously.

DTC Code DTC Detection Condition Trouble Area
B1771 One of the following conditions is met:
  • Occupant classification ECU detects a line short circuit signal, open circuit signal, short circuit to ground signal or short circuit to +B signal in the passenger side buckle switch circuit for 2 seconds.
  • Passenger side buckle switch malfunction.
  • Occupant classification ECU malfunction.
  • Front seat inner belt RH (Front passenger side buckle switch)
  • Front seat wire RH
  • Occupant classification ECU

HINT: