DTC    B1281    Airbag ECU Communication Stop

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DESCRIPTION


HINT:
"Airbag ECU" refers to the center airbag sensor.
This DTC is detected when communication between the center airbag sensor and network gateway ECU stops for more than 10 seconds.

DTC No.
DTC Detection Condition
Trouble Area
B1281
Center airbag sensor communication stops
  1. Center airbag sensor assembly
  2. Wire harness


WIRING DIAGRAM


B108885E03


INSPECTION PROCEDURE

1.CHECK OPERATION

  1. Turn the engine switch on (IG) and check that the SRS warning light illuminates for approximately 6 seconds.

  1. Start the engine and check that the SRS warning light on the combination meter turns off.



NG
Go to step 2
OK

REPLACE AIRBAG SENSOR ASSEMBLY CENTER 

2.CHECK WIRE HARNESS (CENTER AIRBAG SENSOR ASSEMBLY - BATTERY AND BODY GROUND)
B109179E03

  1. Disconnect the L44 sensor connector.

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

    Standard resistance:
    Tester Connection
    		Condition
    		Specified Condition
    L44-25 (E1) - Body ground
    		Always
    		Below 1 Ω

    Standard voltage:
    Tester Connection
    		Condition
    		Specified Condition
    L44-21 (IG2) - Body ground
    		Engine switch on (IG)
    		10 to 14 V



NG
REPAIR OR REPLACE HARNESS AND CONNECTOR
OK


3.CHECK RESISTANCE OF COMMUNICATION LINE

E109789E03

  1. Disconnect the L44 sensor connector.

  1. Disconnect the L31 meter connector.

  1. Disconnect the L52 amplifier connector.

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

    Standard resistance:
    Tester Connection
    		Specified Condition
    L44-13 (MPX1) - L31-5 (MPX-)
    		Below 1 Ω
    L44-22 (MPX2) - L52-30 (MPX+)
    		Below 1 Ω

    Result:
    Result
    		Proceed to
    Both are OK
    		A
    One is OK
    		B
    Both are NG
    		C



B
REPLACE AIRBAG SENSOR ASSEMBLY CENTER AND HARNESS AND CONNECTOR

C
REPAIR OR REPLACE HARNESS AND CONNECTOR
A

REPLACE CENTER AIRBAG SENSOR ASSEMBLY