B1212

MULTIPLEX COMMUNICATION: MULTIPLEX COMMUNICATION SYSTEM: B1212: Front Passenger Door ECU Communication Stop

DTC B1212 - Front Passenger Door ECU Communication Stop

DESCRIPTION
- This DTC is detected when communication between the multiplex network door ECU front RH (front passenger side door ECU) and the network gateway ECU stops for more than 10 seconds.





WIRING DIAGRAM





INSPECTION PROCEDURE

PROCEDURE

1. CHECK WIRE HARNESS (MULTIPLEX NETWORK DOOR ECU FRONT RH (FRONT PASSENGER SIDE DOOR ECU) - BATTERY AND BODY GROUND)




(a) Disconnect the M4 ECU connector.
(b) Measure the voltage and resistance of the wire harness side connector.
Standard voltage:






Standard resistance:






NG -- REPAIR OR REPLACE HARNESS AND CONNECTOR
OK -- Continue to next step.

2. CHECK RESISTANCE OF COMMUNICATION LINE




(a) Disconnect the M4, O3, U28 and Q6 ECU connectors.
(b) Disconnect the a7 switch connector.
(c) Measure the resistance of the wire harness side connectors.
Standard resistance:






Result:






C -- REPAIR OR REPLACE HARNESS AND CONNECTOR
B -- REPLACE MULTIPLEX NETWORK DOOR ECU FRONT RH AND WIRE HARNESS CONNECTOR
A -- REPLACE MULTIPLEX NETWORK DOOR ECU FRONT RH (PASSENGER DOOR ECU)