Dtc B1297 Clearance Sonar Ecu Communication Stop

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

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

CHECK OPERATION

INSPECT FUSE (LH-IG)

CHECK WIRE HARNESS (CLEARANCE SONAR ECU - BODY GROUND)

CHECK RESISTANCE OF COMMUNICATION LINE

DTC B1297 Clearance Sonar ECU Communication Stop


DESCRIPTION


DTC No.
DTC Detection Condition
Trouble Area
B1297
Clearance warning ECU assembly communication stops
  1. Clearance warning ECU assembly
  2. Wire harness

WIRING DIAGRAM


Lexus Gs430, Gs300. Uzs190 Grs190.Multiplex Communication.Multiplex Communication System. Dtc B1297 Clearance Sonar Ecu Communication Stop


INSPECTION PROCEDURE

1.CHECK OPERATION

  1. Turn the engine switch on (IG) and the clearance sonar main switch ON. Check that the combination meter displays the graphic of the system check operation for approximately 2 seconds as it checks for an open circuit and a malfunction in the sensor. Also, check that the buzzer emits a sound for approximately 1 second.

    OK:
    System check graphic is displayed on combination meter for approximately 2 seconds and buzzer sound is emitted for approximately 1 second.


NG
Go to step 2
OK

REPLACE CLEARANCE SONAR ECU

2.INSPECT FUSE (LH-IG)

  1. Remove the LH-HG fuse from the junction block.

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

    Standard resistance:
    Below 1 Ω


NG
REPLACE FUSE
OK


3.CHECK WIRE HARNESS (CLEARANCE SONAR ECU - BODY GROUND)
Lexus Gs430, Gs300. Uzs190 Grs190.Multiplex Communication.Multiplex Communication System. Dtc B1297 Clearance Sonar Ecu Communication Stop

  1. Disconnect the A40 ECU connector.

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

    Standard voltage:
    Tester Connection
    		Condition
    		Specified Condition
    A40-8 (IG) - Body ground
    		Engine switch off→on (IG)
    		0 V → 10 to 14 V
    Standard resistance:
    Tester Connection
    		Condition
    		Specified Condition
    A40-26 (M+) - Body ground
    		Constant
    		Below 1 Ω


NG
REPAIR OR REPLACE HARNESS AND CONNECTOR
OK


4.CHECK RESISTANCE OF COMMUNICATION LINE

Lexus Gs430, Gs300. Uzs190 Grs190.Multiplex Communication.Multiplex Communication System. Dtc B1297 Clearance Sonar Ecu Communication Stop

  1. Disconnect the A40 ECU connector.

  1. Disconnect the L66 ECU connector.

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

    Standard resistance:
    Tester Connection
    		Specified Condition
    A40-26 (M+) - L66-4 (MPI1)
    		Below 1 Ω


NG
REPAIR OR REPLACE HARNESS AND CONNECTOR
OK

REPLACE CLEARANCE SONAR ECU