Last Modified: 04-05-2023 6.11:8.1.0 Doc ID: RM100000000VJT7
Model Year Start: 2016 Model: Sienna Prod Date Range: [12/2015 - 11/2017]
Title: PRE-COLLISION: PRE-COLLISION SYSTEM: B2074,B2075; Driver Side Seat Belt Buckle Switch Circuit Malfunction; 2016 - 2017 MY Sienna [12/2015 - 11/2017]

DTC

B2074

Driver Side Seat Belt Buckle Switch Circuit Malfunction

DTC

B2075

Passenger Side Seat Belt Buckle Switch Circuit Malfunction

DESCRIPTION

These DTCs are stored when a malfunction is detected in the driver side buckle switch circuit or passenger side buckle switch circuit.

DTC No.

DTC Detection Condition

Trouble Area

B2074

Malfunction in front seat belt inner LH

  • Wire harness or connector
  • Front seat inner belt LH assembly
  • Center airbag sensor assembly
  • Seat belt control ECU
  • Power management control ECU*1
  • Network gateway ECU*2

B2075

Malfunction in front seat belt inner RH

  • Wire harness or connector
  • Front seat inner belt RH assembly
  • Occupant classification ECU
  • Center airbag sensor assembly
  • Seat belt control ECU
  • Power management control ECU*1
  • Network gateway ECU*2

*1: w/ Smart Key System

*2: w/o Smart Key System

WIRING DIAGRAM

CAUTION / NOTICE / HINT

HINT:

This circuit uses CAN communication. Therefore, be sure to check that the CAN communication system is normal before performing inspection (See page 2016 MY Sienna [12/2015 - 08/2016]; NETWORKING: CAN COMMUNICATION SYSTEM: HOW TO PROCEED WITH TROUBLESHOOTING 2017 MY Sienna [08/2016 - 11/2017]; NETWORKING: CAN COMMUNICATION SYSTEM: HOW TO PROCEED WITH TROUBLESHOOTING ).

PROCEDURE

1.

CHECK FOR DTC (CAN COMMUNICATION SYSTEM)

(a) Clear the DTCs (See page 2016 MY Sienna [12/2015 - 08/2016]; NETWORKING: CAN COMMUNICATION SYSTEM: HOW TO PROCEED WITH TROUBLESHOOTING 2017 MY Sienna [08/2016 - 11/2017]; NETWORKING: CAN COMMUNICATION SYSTEM: HOW TO PROCEED WITH TROUBLESHOOTING ).

(b) Check for DTCs (See page 2016 MY Sienna [12/2015 - 08/2016]; NETWORKING: CAN COMMUNICATION SYSTEM: HOW TO PROCEED WITH TROUBLESHOOTING 2017 MY Sienna [08/2016 - 11/2017]; NETWORKING: CAN COMMUNICATION SYSTEM: HOW TO PROCEED WITH TROUBLESHOOTING ).

OK:

CAN communication system DTC is not output.

NG

GO TO CAN COMMUNICATION SYSTEM

(See page 2016 MY Sienna [12/2015 - 08/2016]; NETWORKING: CAN COMMUNICATION SYSTEM: HOW TO PROCEED WITH TROUBLESHOOTING 2017 MY Sienna [08/2016 - 11/2017]; NETWORKING: CAN COMMUNICATION SYSTEM: HOW TO PROCEED WITH TROUBLESHOOTING )

OK

2.

CHECK FOR DTC (AIRBAG SYSTEM)

(a) Check DTCs for the airbag system (See page 2016 - 2020 MY Sienna [12/2015 -        ]; SUPPLEMENTAL RESTRAINT SYSTEMS: AIRBAG SYSTEM: DTC CHECK / CLEAR ).

OK:

Airbag system DTC is not output.

NG

GO TO AIRBAG SYSTEM

OK

3.

CHECK FOR DTC (OCCUPANT CLASSIFICATION SYSTEM)

(a) Check DTCs for the occupant classification system (See page 2016 - 2020 MY Sienna [12/2015 -        ]; SUPPLEMENTAL RESTRAINT SYSTEMS: OCCUPANT CLASSIFICATION SYSTEM: DTC CHECK / CLEAR ).

OK:

DTC B1771 is not output.

Result

Result

Proceed to

DTC B1771 is not output (w/ Smart Key System)

A

DTC B1771 is not output (w/o Smart Key System)

B

DTC B1771 is output

C

B

GO TO STEP 6

C

GO TO OCCUPANT CLASSIFICATION SYSTEM

A

4.

REPLACE POWER MANAGEMENT CONTROL ECU

(a) Replace the power management control ECU (See page 2016 - 2017 MY Sienna [12/2015 - 11/2017]; POWER DISTRIBUTION: POWER MANAGEMENT CONTROL ECU: REMOVAL ).

NEXT

5.

CHECK FOR DTC (PRE-COLLISION SYSTEM)

(a) Using the Techstream, enter the following menus: Body Electrical / Pre-Collision / Trouble Codes.

(b) Clear the DTCs (See page 2016 - 2017 MY Sienna [12/2015 - 11/2017]; PRE-COLLISION: PRE-COLLISION SYSTEM: DTC CHECK / CLEAR ).

(c) Check for DTCs (See page 2016 - 2017 MY Sienna [12/2015 - 11/2017]; PRE-COLLISION: PRE-COLLISION SYSTEM: DTC CHECK / CLEAR ).

OK:

DTC B2074 or B2075 is not output.

OK

END

NG

REPLACE SEAT BELT CONTROL ECU

6.

REPLACE NETWORK GATEWAY ECU

(a) Replace the network gateway ECU (See page 2016 - 2017 MY Sienna [12/2015 - 11/2017]; NETWORKING: NETWORK GATEWAY ECU: REMOVAL ).

NEXT

7.

CHECK FOR DTC (PRE-COLLISION SYSTEM)

(a) Using the Techstream, enter the following menus: Body Electrical / Pre-Collision / Trouble Codes.

(b) Clear the DTCs (See page 2016 - 2017 MY Sienna [12/2015 - 11/2017]; PRE-COLLISION: PRE-COLLISION SYSTEM: DTC CHECK / CLEAR ).

(c) Check for DTCs (See page 2016 - 2017 MY Sienna [12/2015 - 11/2017]; PRE-COLLISION: PRE-COLLISION SYSTEM: DTC CHECK / CLEAR ).

OK:

DTC B2074 or B2075 is not output.

OK

END

NG

REPLACE SEAT BELT CONTROL ECU