B1200

MULTIPLEX COMMUNICATION: MULTIPLEX COMMUNICATION SYSTEM: B1200: MPX Body ECU Stop
B1200 - MPX Body ECU Stop

DESCRIPTION

* This DTC is detected when communication between the main body ECU RH (cowl side J/B RH) and 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 B1200, repair the "+B or GND short malfunction of communication bus" DTCs first.

PROCEDURE

1. INSPECT FUSE (FR DOOR RH)

(a) Remove the FR DOOR RH fuse from the cowl side J/B RH.

(b) Measure the resistance of the fuse.

Standard resistance:

Below 1 Ohms

NG -- REPLACE FUSE
OK -- Continue to next step.

2. CHECK WIRE HARNESS (MAIN BODY ECU RH - BATTERY AND BODY GROUND)

(a) Disconnect the main body ECU RH 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 J75 and RJ ECU connectors.





(b) Disconnect the J76 ECU connector.

(c) Disconnect the P33 ECU connector.

(d) Measure the resistance between the specified terminals on the wire harness side connectors.

Standard resistance:





Result:





B -- REPLACE BODY ECU AND REPAIR OR REPLACE HARNESS OR CONNECTOR

C -- REPAIR OR REPLACE HARNESS OR CONNECTOR

A -- REPLACE BODY ECU