Last Modified: 04-05-2023 6.11:8.1.0 Doc ID: RM100000000ZY3F
Model Year Start: 2017 Model: Sienna Prod Date Range: [08/2016 -           ]
Title: MF1A (TRANSFER / 4WD / AWD): ACTIVE TORQUE CONTROL 4WD SYSTEM: TC and CG Terminal Circuit; 2017 - 2020 MY Sienna [08/2016 -        ]

TC and CG Terminal Circuit

DESCRIPTION

Connecting terminals TC and CG of the DLC3 causes the 4WD control ECU to display 2-digit DTCs by flashing the AWD warning light.

HINT:

When each warning light remains blinking, a short to ground in the wiring of terminal TC of the DLC3 or an internal short to ground in each ECU is suspected.

WIRING DIAGRAM

CAUTION / NOTICE / HINT

HINT:

Check the condition of each related circuit connector before troubleshooting (See page 2016 - 2020 MY Sienna [12/2015 -        ]; INTRODUCTION: HOW TO TROUBLESHOOT ECU CONTROLLED SYSTEMS: ELECTRONIC CIRCUIT INSPECTION PROCEDURE ).

PROCEDURE

1.

CHECK FOR DTC (CAN COMMUNICATION SYSTEM)

(a) Check if the CAN communication DTC is output (See page 2017 MY Sienna [08/2016 - 11/2017]; NETWORKING: CAN COMMUNICATION SYSTEM: DIAGNOSIS SYSTEM 2018 MY Sienna [11/2017 - 08/2018]; NETWORKING: CAN COMMUNICATION SYSTEM: DIAGNOSIS SYSTEM 2019 - 2020 MY Sienna [08/2018 -        ]; NETWORKING: CAN COMMUNICATION SYSTEM: DIAGNOSIS SYSTEM ).

Result

Result

Proceed to

DTC is not output

A

DTC is output

B
B

REPAIR CAN COMMUNICATION SYSTEM

(See page 2017 MY Sienna [08/2016 - 11/2017]; NETWORKING: CAN COMMUNICATION SYSTEM: HOW TO PROCEED WITH TROUBLESHOOTING 2018 - 2020 MY Sienna [11/2017 -        ]; NETWORKING: CAN COMMUNICATION SYSTEM: HOW TO PROCEED WITH TROUBLESHOOTING )
A

2.

CHECK HARNESS AND CONNECTOR (TC OF DLC3 - TC OF ECM AND BODY GROUND)

(a) Turn the ignition switch off.

(b) Disconnect the A69 ECM connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

D16-13 (TC) - A69-33 (TC)

Always

Below 1 Ω

D16-13 (TC) - Body Ground

Always

10 kΩ or higher
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

3.

CHECK HARNESS AND CONNECTOR (CG OF DLC3 - BODY GROUND)

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

D16-4 (CG) - Body ground

Always

Below 1 Ω
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

4.

CHECK HARNESS AND CONNECTOR (TC OF DLC3 - BODY GROUND)

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

D16-13 (TC) - Body ground

Always

10 kΩ or higher
OK

REPLACE 4WD CONTROL ECU

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR