B1272

MULTIPLEX COMMUNICATION: MULTIPLEX COMMUNICATION SYSTEM: B1272: Power Seat ECU Communication Stop

DTC B1272 - Power Seat ECU Communication Stop

DESCRIPTION

This DTC is detected when communication between the position control ECU and switch (driver seat ECU) and network gateway ECU stops for more than 10 seconds.






WIRING DIAGRAM





INSPECTION PROCEDURE

PROCEDURE

1. CHECK OPERATION
(a) Check that the manual switch of the front power seat can move the driver side seat normally.
OK:
Manual switch of the front power seat can move driver side seat normally.
NG -- CHECK WIRE HARNESS (POSITION CONTROL ECU AND SWITCH ASSEMBLY (DRIVER SEAT ECU) - BATTERY AND BODY GROUND)
OK -- REPLACE POSITION CONTROL ECU AND SWITCH ASSEMBLY (DRIVER SEAT ECU)
2. CHECK WIRE HARNESS (POSITION CONTROL ECU AND SWITCH ASSEMBLY (DRIVER SEAT ECU) - BATTERY AND BODY GROUND)





(a) Disconnect the b7and b8 ECU connectors.
(b) Measure the resistance and voltage of the wire harness side connectors.
Standard Resistance:






Standard Voltage:






NG -- REPAIR OR REPLACE HARNESS AND CONNECTOR
OK -- Continue to next step.
3. CHECK RESISTANCE OF COMMUNICATION LINE





(a) Disconnect the V3 and b7 ECU connectors.
(b) Measure the resistance of the wire harness side connectors.
Standard resistance:






NG -- REPAIR OR REPLACE HARNESS AND CONNECTOR
OK -- REPLACE POSITION CONTROL ECU AND SWITCH ASSEMBLY