Dtc B1273 Sliding Roof Ecu Communication Stop

Communication System. Lexus Is250, Is220D. Gse20 Ale20
Multiplex Communication. Lexus Is250, Is220D. Gse20 Ale20

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

INSPECT FUSE (S/ROOF)

CHECK WIRE HARNESS (SLIDING ROOF CONTROL ECU - BATTERY AND BODY GROUND)

CHECK RESISTANCE OF COMMUNICATION LINE

DTC B1273 Sliding Roof ECU Communication Stop


DESCRIPTION

This DTC is detected when communication between the sliding roof control ECU and gateway ECU stops for more than 10 seconds.

DTC No.
DTC Detection Condition
Trouble Area
B1273
Sliding roof control ECU communication stops
  1. Sliding roof control ECU
  2. Wire harness

WIRING DIAGRAM


Lexus Is250, Is220D. Gse20 Ale20.Multiplex Communication.Multiplex Communication System. Dtc B1273 Sliding Roof Ecu Communication Stop


INSPECTION PROCEDURE

HINT:
When "+B of GND short malfunction of communication bus" DTCs (B1214 and B1215) are detected at the same time as "communication stop" DTCB1273, repair the "+B or GND short malfunction of communication bus" DTCs first.
1.INSPECT FUSE (S/ROOF)

  1. Remove the S/ROOF fuse from the main body ECU LH (cowl side J/B LH).

  1. Measure the resistance of the fuse.

    Standard resistance:
    Below 1 Ω


NG
REPLACE FUSE
OK


2.CHECK WIRE HARNESS (SLIDING ROOF CONTROL ECU - BATTERY AND BODY GROUND)


    Lexus Is250, Is220D. Gse20 Ale20.Multiplex Communication.Multiplex Communication System. Dtc B1273 Sliding Roof Ecu Communication Stop

  1. Disconnect the R6 ECU connector.

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

    Standard voltage:
    Tester Connection
    		Condition
    		Specified Condition
    B (R6-5) - Body ground
    		Always
    		10 to 14 V
    Standard resistance:
    Tester Connection
    		Specified Condition
    E (R6-7) - Body ground
    		Below 1 Ω


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


3.CHECK RESISTANCE OF COMMUNICATION LINE


    Lexus Is250, Is220D. Gse20 Ale20.Multiplex Communication.Multiplex Communication System. Dtc B1273 Sliding Roof Ecu Communication Stop

  1. Disconnect the R6 and R5 connectors.

  1. Measure the resistance between the specified terminals on the wire harness side connectors.

    Standard resistance:
    Tester Connection
    		Specified Condition
    MPX1 (R6-10) - MPX2 (R5-38)
    		Below 1 Ω
    MPX1 (R6-10) - Body ground
    		10 kΩ or higher


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

REPLACE SLIDING ROOF CONTROL ECU