Dtc B1248 Avc-Lan Communication Impossible

Communication System. Lexus Gs430, Gs300. Uzs190 Grs190
Multiplex Communication. Lexus Gs430, Gs300. Uzs190 Grs190

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

CHECK OPERATION

CHECK RESISTANCE OF COMMUNICATION LINE

DTC B1248 AVC-LAN Communication Impossible


DESCRIPTION

This DTC is detected when communication is impossible between the radio and player ECU and gateway ECU.

DTC No.
DTC Detection Condition
Trouble Area
B1248
AVC-LAN communication is impossible
  1. Radio and player ECU
  2. Wire harness

WIRING DIAGRAM


Lexus Gs430, Gs300. Uzs190 Grs190.Multiplex Communication.Multiplex Communication System. Dtc B1248 Avc-Lan Communication Impossible


INSPECTION PROCEDURE

1.CHECK OPERATION

  1. Check that the steering pad switch can operate the audio system normally.

    OK:
    Steering pad switch can operate audio system normally.


NG
Go to step 2
OK

REPLACE RADIO AND PLAYER ECU

2.CHECK RESISTANCE OF COMMUNICATION LINE

Lexus Gs430, Gs300. Uzs190 Grs190.Multiplex Communication.Multiplex Communication System. Dtc B1248 Avc-Lan Communication Impossible

  1. Disconnect the L56 and L66 ECU connectors.

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

    Standard resistance:
    Tester Connection
    		Specified Condition
    L56-9 (TX+) - L66-6 (GTX+)
    		Below 1 Ω
    L56-10 (TX-) - L66-21 (GTX-)
    		Below 1 Ω
    Result:
    Result
    		Proceed to
    Both are OK
    		A
    One or two is OK
    		B
    Both are NG
    		C


B
REPLACE RADIO AND PLAYER ECU AND REPAIR OR REPLACE HARNESS AND CONNECTOR

C
REPAIR OR REPLACE HARNESS AND CONNECTOR
A

REPLACE RADIO AND PLAYER ECU