Toyota Sienna Service Manual: Airbag ECU Communication Stop

Toyota Sienna Service Manual / Multiplex communication / System description / Diagnostic trouble code chart / Airbag ECU Communication Stop

DTC B1281 Airbag ECU Communication Stop

DESCRIPTION

DTC B1281 is output when communication between the airbag ECU and the multiplex network gateway ECU stops for more than 10 seconds.

DTC No.	DTC Detection Condition	Trouble Area
B1281	Airbag ECU communication stops	Airbag sensor assembly Wire harness

WIRING DIAGRAM

WIRING DIAGRAM

INSPECTION PROCEDURE

1 CHECK HARNESS AND CONNECTOR (AIRBAG SENSOR ASSEMBLY - BATTERY)

CHECK HARNESS AND CONNECTOR (AIRBAG SENSOR ASSEMBLY - BATTERY)

Disconnect the A21 ECU connector.
Measure the voltage according to the value(s) in the table below.

Standard voltage

Standard voltage

2 CHECK HARNESS AND CONNECTOR (AIRBAG SENSOR ASSEMBLY - GROUND)

CHECK HARNESS AND CONNECTOR (AIRBAG SENSOR ASSEMBLY - GROUND)

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

Standard resistance

Standard resistance

3 CHECK COMMUNICATION LINE

CHECK COMMUNICATION LINE

Disconnect the 1E and A9 ECU connectors.
Measure the resistance according to the value(s) in the table below.

Standard resistance

Standard resistance

HINT:
*1: for Automatic A/C
*2: for Manual A/C

Result

Result

REPLACE AIRBAG SENSOR ASSEMBLY

Power Seat ECU Communication Stop

DTC B1272 Power Seat ECU Communication Stop DESCRIPTION This DTC is detected when communication between the seat position control ECU and the multiplex network gateway ECU stops for more than 10 ...

Back Door ECU Communication Stop

DTC B1287 Back Door ECU Communication Stop DESCRIPTION DTC B1287 is output when communication between the power back door ECU and the multiplex network gateway ECU stops for more than 10 seconds. ...

Other materials:

ABS Warning Light Remains ON
DESCRIPTION If any of the following is detected, the ABS warning light remains on. The skid control ECU connectors are disconnected from the skid control ECU. There is a malfunction in the skid control ECU internal circuit. There is an open in the harness between the combination meter an ...

Data list / active test
1. USING INTELLIGENT TESTER Connect the intelligent tester to the DLC3. Monitor the ECU data by following the prompts on the tester screen. HINT: The intelligent tester has a "Snapshot" function which records the monitored data. Refer to the intelligent tester o ...

Before refueling the vehicle
Close all the doors and windows, and turn the engine switch to the “LOCK” position (vehicles without a smart key system) or off (vehicles with a smart key system). Confirm the type of fuel. Fuel type Fuel tank opening for unleaded gasoline To help prevent incorrect fueling, your ve ...