B1772: Seat Position Sensor Circuit Malfunction: Description

WARNING: This page is about a different car, the 2007 Toyota Land Cruiser. However, it is still accessible from the selected car via links, so may be relevant.

The seat position sensor circuit consists of the occupant classification ECU and the seat position sensor. The seat position sensor sends the seat position signal to the occupant classification ECU to control the dual stage deployment of the front passenger airbag.

DTC B1772 is recorded when a malfunction is detected in the seat position sensor circuit.

DIAGNOSTIC TROUBLE CODE TABLE

DTC No.	DTC Detection Condition	Trouble Area
B1772	When 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 seat position sensor circuit for 2 seconds. Seat position sensor malfunction Occupant classification ECU malfunction	No. 1 seat wire Seat position sensor Occupant classification ECU

NOTE: Replace the occupant classification ECU, occupant classification sensor, seat cushion cover pad, seat cushion cover and seat cushion seat heater as a 5 part set (see supply set part no.).

HINT:

When DTC B1650/32 is detected as a result of troubleshooting the supplemental restraint system, check the DTCs stored in the occupant classification ECU, and perform troubleshooting for those DTCs first.
Use the intelligent tester to check for DTCs of the occupant classification ECU, otherwise the DTC cannot be read.