DTC    B1200    MPX Body ECU Stop

for Preparation Click here


DESCRIPTION

  1. This DTC is detected when communication between the instrument panel junction block (multiplex network body ECU) and multiplex network gateway ECU stops for more than 10 seconds.

DTC No.
DTC Detection Condition
Trouble Area
B1200
Multiplex network body ECU Communication stops
  1. Instrument panel junction block (multiplex network body ECU)
  2. Wire harness

WIRING DIAGRAM


B110986E02


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.

1.CHECK OPERATION

  1. Check if the wireless door lock control function operates normally through the wireless transmitter.

    HINT:
    With this inspection, the multiplex network body ECU CPU can be diagnosed if it works normally or not.

    OK:
    Wireless door lock function operates normally.



OK
Go to step 4
NG


2.INSPECT FUSE (EUC-B No.1)

  1. Remove the ECU No.1 fuse from the fusible link block.

  1. Measure the resistance of the fuse.

    Standard resistance:
    Below 1 Ω



NG
REPLACE FUSE
OK


3.CHECK WIRE HARNESS (MULTIPLEX NETWORK BODY ECU - BATTERY AND BODY GROUND)


  1. Disconnect the 1D and 1F instrument panel junction block connectors.


    B111045E01

  1. Measure the resistance and voltage of the wire harness side connectors.

    Standard voltage:
    Tester Connection
    		Specified Condition
    1D-10 (BECU) - Body ground
    		10 to 14 V

    Standard resistance:
    Tester Connection
    		Specified Condition
    1F-10 (GND1) - Body ground
    		Below 1 Ω



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


4.CHECK RESISTANCE OF COMMUNICATION LINE

  1. Disconnect the 1E fusible link block connector.

  1. Disconnect the B7 and T9 ECU connectors.



  1. Disconnect the P19 switch connector.


    B111046E02

  1. Measure the resistance of the wire harness side connectors.


Standard resistance:

Tester Connection
Specified Condition
1E-7 (MPX1) - P19-8 (MPX2)
Below 1 Ω
B7-21 (MPX2) - T9-4 (MPX1)
Below 1 Ω



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

REPLACE INSTRUMENT PANEL JUNCTION BLOCK (MULTIPLEX NETWORK BODY ECU)