B1272

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

DESCRIPTION

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





WIRING DIAGRAM





INSPECTION PROCEDURE

HINT
If "+B of GND short malfunction of communication bus" DTCs (B1214 and B1215) are detected at the same time as "communication stop" DTC B1272, repair the "+B or GND short malfunction of communication bus" DTCs first B1214.

PROCEDURE

1. INSPECT FUSE (FR P/SEAT LH, MPX-B)

(a) Remove the FR P/SEAT LH fuse from the cowl side junction block LH.

(b) Remove the MPX-B fuse from the engine room relay block No. 1.

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

Standard Resistance:





NG -- REPLACE FUSE (FR P/SEAT LH, MPX-B)
OK -- Continue to next step.

2. CHECK HARNESS AND CONNECTOR (FRONT POWER SEAT SWITCH - BATTERY AND BODY GROUND)

(a) Disconnect the U6 and U7 connector.





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

Standard Voltage:





Standard Resistance:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR (FRONT POWER SEAT SWITCH - BATTERY AND BODY GROUND)
OK -- Continue to next step.

3. CHECK HARNESS AND CONNECTOR (COMMUNICATION LINE)

(a) Disconnect the U7, 2F and J55 connectors.





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

Standard Resistance:





NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR

OK -- REPLACE FRONT POWER SEAT SWITCH LH Removal