Dtc B2785 Communication Malfunction Between Ecus Connected By Lin

Securities. Lexus Gs430, Gs300. Uzs190 Grs190
Engine Immobiliser. Lexus Gs430, Gs300. Uzs190 Grs190

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

CHECK FOR DTC

CHECK WIRE HARNESS (LIN COMMUNICATION LINE AND BODY GROUND)

CHECK OPERATION OF CERTIFICATION ECU

CHECK OPERATION OF POWER SOURCE CONTROL ECU

CHECK STEERING LOCK ECU

DTC B2785 Communication Malfunction between ECUs Connected by LIN


DESCRIPTION

This DTC is output when LIN communication from the certification ECU stops for a certain amount of time.

DTC No.
DTC Detection Condition
Trouble Area
B2785
LIN communication from certification ECU stops for certain amount of time
  1. Open or short in wire harness between ECUs
  1. Wire harness
  2. Certification ECU
  3. Immobiliser code ECU
  4. Power source control ECU
  5. Steering lock ECU

WIRING DIAGRAM


Lexus Gs430, Gs300. Uzs190 Grs190.Engine Immobiliser.Engine Immobiliser System. Dtc B2785 Communication Malfunction Between Ecus Connected By Lin


INSPECTION PROCEDURE

1.CHECK FOR DTC

  1. Delete the DTC (Click here).

  1. Recheck for DTC.

    Result:
    Result
    		Proceed to
    B2785 output reoccurs
    		A
    B2785 output does not reoccur
    		B


B
NORMAL
A


2.CHECK WIRE HARNESS (LIN COMMUNICATION LINE AND BODY GROUND)

Lexus Gs430, Gs300. Uzs190 Grs190.Engine Immobiliser.Engine Immobiliser System. Dtc B2785 Communication Malfunction Between Ecus Connected By Lin

  1. Disconnect the V28, L28, L73 and L58 ECU connectors.

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

    Standard resistance:
    Tester Connection
    		Specified Condition
    V28-10 (LIN) - L58-3 (LIN)
    		Below 1 Ω
    V28-10 (LIN) - L73-30 (LIN1)
    		Below 1 Ω
    V28-10 (LIN) - L28-5 (LIN1)
    		Below 1 Ω
    V28-10 (LIN), L58-3 (LIN), L73-30 (LIN1) or L28-5 (LIN1) - Body ground
    		10 kΩ or higher


NG
REPAIR OR REPLACE HARNESS AND CONNECTOR
OK


3.CHECK OPERATION OF CERTIFICATION ECU

  1. After replacing the certification ECU with a normal one, check for DTC.

    Result:
    Result
    		Proceed to
    B2785 output reoccurs
    		A
    B2785 output does not reoccur
    		B


B
REPLACE CERTIFICATION ECU
A


4.CHECK OPERATION OF POWER SOURCE CONTROL ECU

  1. After replacing the power source control ECU with a normal one, check for DTC.

    Result:
    Result
    		Proceed to
    B2785 output reoccurs
    		A
    B2785 output does not reoccur
    		B


B
REPLACE POWER SOURCE CONTROL ECU
A


5.CHECK STEERING LOCK ECU

  1. After replacing the steering control ECU with a normal one, check for DTC.

    Result:
    Result
    		Proceed to
    B2785 output reoccurs
    		A
    B2785 output does not reoccur
    		B


B
REPLACE STEERING LOCK ECU
A

REPLACE IMMOBILISER CODE ECU