DTC    B1273    Sliding Roof ECU Communication Stop

for Preparation Click here


DESCRIPTION

This DTC is stored when LIN communication between the sliding roof ECU (sliding roof drive gear assembly) and main body ECU (multiplex network body ECU) stops for 10 seconds or more.

DTC No.
DTC Detection Condition
Trouble Area
B1273
No communication between sliding roof ECU (sliding roof drive gear assembly) and main body ECU (multiplex network body ECU) for 10 seconds or more.
  1. Sliding roof ECU (sliding roof drive gear assembly)
  2. Main body ECU (multiplex network body ECU)
  3. Instrument panel junction block assembly
  4. Wire harness or connector
  5. S/ROOF fuse

WIRING DIAGRAM


B270979E01


INSPECTION PROCEDURE

NOTICE:
  1. Inspect the fuses for circuits related to this system before performing the following inspection procedure.
  2. When the sliding roof ECU (sliding roof drive gear assembly) is replaced or removed and reinstalled, it requires initialization (Click here).
  3. When using the intelligent tester to troubleshoot with the power switch off:
    Connect the intelligent tester to the DLC3, and turn the courtesy switch on and off at 1.5-second intervals until communication between the intelligent tester and vehicle begins.

1.INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY


  1. Remove the instrument panel junction block assembly (Click here).


    B217444E15

  1. Remove the main body ECU (multiplex network body ECU) from the instrument panel junction block assembly.

  1. Measure the resistance according to the value(s) in the table below.

    HINT:
    This inspection is to check the LIN line in the instrument panel junction block assembly that connects the wire harness to the built-in main body ECU (multiplex network body ECU).


    Standard Resistance:

    Tester Connection
    		Condition
    		Specified Condition
    2A-27 (LIN2)- MB-16 (LIN2)
    		Always
    		Below 1 Ω
    2A-27 (LIN2) - Body ground
    		Always
    		10 kΩ or higher


    Text in Illustration 
    *a
    		Component without harness connected
    (Instrument Panel Junction Block Assembly)
    		*b
    		Component without harness connected
    (Instrument Panel Junction Block Assembly)



NG
REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY (Click here)
OK


2.CHECK HARNESS AND CONNECTOR (MAIN BODY ECU - SLIDING ROOF ECU)

  1. Disconnect the T10 sliding roof ECU (sliding roof drive gear assembly) connector.

  1. Measure the resistance according to the value(s) in the table below.

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    2A-27 (LIN2) - T10-4 (LIN)
    		Always
    		Below 1 Ω
    2A-27 (LIN2) - Body ground
    		Always
    		10 kΩ or higher



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


3.CHECK HARNESS AND CONNECTOR (SLIDING ROOF ECU - BATTERY, BODY GROUND)

  1. Measure the voltage according to the value(s) in the table below.

    Standard Voltage:
    Tester Connection
    		Condition
    		Specified Condition
    T10-1 (B) - T10-2 (E)
    		Power switch off
    		11 to 14 V

  1. Measure the resistance according to the value(s) in the table below.

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    T10-2 (E) - Body ground
    		Always
    		10 kΩ or higher



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


4.REPLACE SLIDING ROOF ECU (SLIDING ROOF DRIVE GEAR ASSEMBLY)

  1. Replace the sliding roof ECU (sliding roof drive gear assembly) (Click here).


NEXT


5.CHECK DTC OUTPUT

  1. Clear the DTC (Click here).

  1. Recheck for DTCs.

    OK:
    DTC B1273 is not output.



NG
REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) (Click here)
OK

END (SLIDING ROOF ECU WAS DEFECTIVE)