Dtc B1205 Afs Ecu Communication Stop

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

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

INSPECT FUSE (H-LP LVL)

CHECK WIRE HARNESS (HEADLIGHT SWIVEL ECU ASSEMBLY (AFS ECU) - BATTERY AND BODY GROUND)

CHECK RESISTANCE OF COMMUNICATION LINE

DTC B1205 AFS ECU Communication Stop


DESCRIPTION

  1. This DTC is detected when communication between the headlight swivel ECU (AFS ECU) and the gateway ECU stops for more than 10 seconds.

DTC No.
DTC Detection Condition
Trouble Area
B1205
Headlight swivel ECU communication stops
  1. Headlight swivel ECU assembly (AFS ECU)
  1. Wire harness

WIRING DIAGRAM


Lexus Gs430, Gs300. Uzs190 Grs190.Multiplex Communication.Multiplex Communication System. Dtc B1205 Afs Ecu Communication Stop


INSPECTION PROCEDURE

1.INSPECT FUSE (H-LP LVL)

  1. Remove the H-LP LVL fuse from the cowl side junction block LH.

  1. Measure the resistance of the fuse.

    Standard:
    Below 1 Ω


NG
REPLACE FUSE
OK


2.CHECK WIRE HARNESS (HEADLIGHT SWIVEL ECU ASSEMBLY (AFS ECU) - BATTERY AND BODY GROUND)
Lexus Gs430, Gs300. Uzs190 Grs190.Multiplex Communication.Multiplex Communication System. Dtc B1205 Afs Ecu Communication Stop

  1. Disconnect the A31 ECU connector.

  1. Turn the engine switch on (IG).

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

    Standard voltage:
    Tester Connection
    		Specified Condition
    A31-2 (IG) - Body ground
    		10 to 14 V
    Standard resistance:
    Tester Connection
    		Specified Condition
    A31-1 (E1) - Body ground
    		Below 1 Ω


NG
REPAIR OR REPLACE HARNESS AND CONNECTOR
OK


3.CHECK RESISTANCE OF COMMUNICATION LINE

Lexus Gs430, Gs300. Uzs190 Grs190.Multiplex Communication.Multiplex Communication System. Dtc B1205 Afs Ecu Communication Stop

  1. Disconnect the A31 and A32 ECU connectors.

  1. Disconnect the 2F relay block connector.

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

    Standard resistance:
    Tester Connection
    		Specified Condition
    A31-5 (MPX1) - A32-6 (MPX4)
    		Below 1 Ω
    A31-6 (MPX2) - 2F-6 (MPX1)
    		Below 1 Ω
    Result:
    Result
    		Proceed to
    Both are OK
    		A
    One is OK
    		B
    Both are NG
    		C


B
REPAIR OR REPLACE HARNESS AND CONNECTOR

C
REPLACE HEADLIGHT SWIVEL ECU ASSEMBLY (AFS ECU) AND REPAIR OR REPLACE HARNESS AND CONNECTOR
A

REPLACE HEADLIGHT SWIVEL ECU ASSEMBLY (AFS ECU)