Toyota Sienna Service Manual: Power Seat ECU Communication Stop

Toyota Sienna Service Manual / Multiplex communication / System description / Diagnostic trouble code chart / Power Seat ECU Communication Stop

DTC B1272 Power Seat ECU Communication Stop

DESCRIPTION

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

DTC No.	DTC Detection Condition	Trouble Area
B1272	Power seat ECU communication stops	Seat position control ECU Wire harness

WIRING DIAGRAM

WIRING DIAGRAM

INSPECTION PROCEDURE

1 CHECK HARNESS AND CONNECTOR (SEAT POSITION CONTROL ECU - BATTERY)

CHECK HARNESS AND CONNECTOR (SEAT POSITION CONTROL ECU - BATTERY)

Disconnect the P58 and P59 ECU connectors.
Measure the voltage according to the value(s) in the table below.

Standard voltage

Standard voltage

2 CHECK HARNESS AND CONNECTOR (SEAT POSITION CONTROL ECU - GROUND)

CHECK HARNESS AND CONNECTOR (SEAT POSITION CONTROL ECU - GROUND)

Measure the resistance according to the value(s) in the table below.

Standard resistance

Standard resistance

3 CHECK COMMUNICATION LINE

CHECK COMMUNICATION LINE

Disconnect the G4 ECU connector.
Measure the resistance according to the value(s) in the table below.

Standard resistance

Standard resistance

Result

Result

REPLACE SEAT POSITION CONTROL ECU

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Other materials:

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