DTC    B1263    Luggage Room Junction Block ECU Communication Stop

for Preparation Click here


DESCRIPTION

This DTC is detected when communication between the No.1 junction block assembly (multiplex network rear ECU) and network gateway ECU stops for more than 10 seconds.

DTC No.
DTC Detection Condition
Trouble Area
B1263
No.1 junction block assembly (multiplex network rear ECU) communication stops
  1. No.1 junction block assembly (multiplex network rear ECU)
  2. Wire harness

WIRING DIAGRAM


B111303E01


INSPECTION PROCEDURE

1.INSPECT FUSE (MPX-B, D/C CUT)

  1. Remove the MPX-B and D/C CUT fuses from the engine room No. 1 relay block.

  1. Measure the resistance of the fuses.



NG
REPLACE FUSE
OK


2.CHECK WIRE HARNESS (NO. 1 JUNCTION BLOCK ASSEMBLY - BATTERY AND BODY GROUND)

E109403E03

  1. Disconnect the LC and LF junction block connectors.

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

    Standard voltage:
    Tester Connection
    		Specified Condition
    LC-15 (ECUB) - Body ground
    		10 to 14 V

    Standard resistance:
    Tester Connection
    		Specified Condition
    LF-1 (PGND) - Body ground
    		Below 1 Ω



NG
REPAIR OR REPLACE HARNESS AND CONNECTOR
OK


3.CHECK RESISTANCE OF COMMUNICATION LINE

B111314E01

  1. Disconnect the L66 connector.

  1. Disconnect the V3 and LC junction block connectors.

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

    Standard resistance:
    Tester Connection
    		Specified Condition
    LC-21 (MPX1) - L66-5 (MPL1)
    		Below 1 Ω
    LC-31 (MPX2) - W3-15 (MPX1)
    		Below 1 Ω

    Result:
    Result
    		Proceed to
    Both are OK
    		A
    One is OK
    		B
    Both are NG
    		C



B
REPLACE NO. 1 JUNCTION BLOCK AND HARNESS AND CONNECTOR

C
REPAIR OR REPLACE HARNESS AND CONNECTOR
A

REPLACE NO. 1 JUNCTION BLOCK ASSEMBLY