B1289

MULTIPLEX COMMUNICATION: MULTIPLEX COMMUNICATION SYSTEM: B1289: Passenger Seat ECU Communication Stop

DTC B1289 - Passenger Seat ECU Communication Stop

SYSTEM DESCRIPTION

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






WIRING DIAGRAM





INSPECTION PROCEDURE
HINT:
When "+B of GND short malfunction of communication bus" DTCs (B1214 and B1215) are detected at the same time as "communication stop" DTC B1289, repair the "+B or GND short malfunction of communication bus" DTCs first.

PROCEDURE

1. INSPECT FUSE (FR P/SEAT RH, MPX-B)
(a) Remove the FR P/ SEAT RH fuse from the cowl side J/B RH.
(b) Remove the MPX-B fuse from engine room J/B No. 1.
(c) Measure the resistance of the fuse.
Standard resistance:
Below 1 Ohms
NG -- REPLACE FUSE
OK -- Continue to next step.
2. CHECK WIRE HARNESS (POSITION CONTROL ECU AND SWITCH - BATTERY AND BODY GROUND)




(a) Disconnect the T7 and T6 ECU connector.
(b) Measure the voltage and resistance of the wire harness side connector.
Standard voltage:






Standard resistance:






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




(a) Disconnect the T7, RJ and P33 ECU connectors.
(b) Measure the resistance between the specified terminals on the wire harness side connectors.
Standard resistance:






Result:






C -- REPAIR OR REPLACE HARNESS OR CONNECTOR
B -- REPAIR OR REPLACE HARNESS OR CONNECTOR AND REPLACE POSITION CONTROL ECU
A -- REPLACE POSITION CONTROL ECU AND SWITCH