B1268

LIGHTING: LIGHTING SYSTEM: B1268: Back-up Communication Bus Malfunction
B1268 - Back-up Communication Bus Malfunction

DESCRIPTION

This DTC is output when a B+ or GND short occurs on the back-up communication bus (BU+, BU-).





WIRING DIAGRAM





INSEPCTION PROCEDURE

PROCEDURE

1. INSPECT LUGGAGE ROOM JUNCTION BLOCK

(a) Disconnect the L24 ECU connector.

(b) Check the DTC.

OK:

DTC B1268 is not output.

OK -- REPLACE LUGGAGE ROOM JUNCTION BLOCK
NG -- Continue to next step.

2. INSPECT TURN SIGNAL SWITCH ASSEMBLY

(a) Connect the L24 ECU connector.

(b) Disconnect the C11 switch connector.

(c) Check the DTC.

OK:

DTC B1268 is not output.

OK -- REPLACE TURN SIGNAL SWITCH ASSEMBLY
NG -- Continue to next step.

3. CHECK WIRE HARNESS (DRIVER SIDE JUNCTION BLOCK ECU - SWITCH)





(a) Disconnect the D4 ECU connector.

(b) Disconnect the C11 switch connector.

(c) Measure the resistance of the wire harness side connectors.

Standard resistance:





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

4. CHECK WIRE HARNESS (DRIVER SIDE JUNCTION BLOCK ECU - LUGGAGE ROOM JUNCTION BLOCK ECU)





(a) Disconnect the D3 ECU connector.

(b) Disconnect the L24 ECU connector.

(c) Measure the resistance of the wire harness side connectors.

Standard resistance:





NG -- REPAIR OR REPLACE HARNESS AND CONNECTOR

OK -- REPLACE DRIVER SIDE JUNCTION BLOCK