Last Modified: 04-05-2023 6.11:8.1.0 Doc ID: RM100000000VIV4
Model Year Start: 2016 Model: Sienna Prod Date Range: [12/2015 - 08/2016]
Title: BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: VEHICLE STABILITY CONTROL SYSTEM: Brake Warning Light Remains ON; 2016 MY Sienna [12/2015 - 08/2016]

Brake Warning Light Remains ON

DESCRIPTION

The skid control ECU is connected to the combination meter via CAN communication.

If any of the following is detected, the brake warning light remains on:

  • The skid control ECU connector is disconnected from the skid control ECU.
  • The brake fluid level is insufficient.
  • The parking brake is applied.
  • EBD operation has been disabled.

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

When replacing the brake actuator assembly, perform zero point calibration and store system information (See page 2016 - 2017 MY Sienna [12/2015 - 11/2017]; BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: VEHICLE STABILITY CONTROL SYSTEM: CALIBRATION ).

PROCEDURE

1.

CHECK CAN COMMUNICATION SYSTEM

(a) Check if a CAN communication system DTC is output (See page 2016 MY Sienna [12/2015 - 08/2016]; NETWORKING: CAN COMMUNICATION SYSTEM: DIAGNOSIS SYSTEM ).

Result

Result

Proceed to

DTC is not output

A

DTC is output

B
B

INSPECT CAN COMMUNICATION SYSTEM

A

2.

CHECK IF SKID CONTROL ECU CONNECTOR IS SECURELY CONNECTED

(a) Check if the skid control ECU connector is securely connected.

OK:

The connector is securely connected.

NG

CONNECT CONNECTOR TO ECU CORRECTLY
OK

3.

INSPECT BATTERY

(a) Check the battery voltage.

Standard voltage:

11 to 14 V

NG

CHECK OR REPLACE CHARGING SYSTEM OR BATTERY

OK

4.

INSPECT SKID CONTROL ECU (IG1 TERMINAL)

(a) Disconnect the skid control ECU connector.

(b) Turn the ignition switch to ON.

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

Standard Voltage:

Tester Connection

Switch Condition

Specified Condition

A4-34 (IG1) - Body ground

Ignition switch ON

11 to 14 V

Text in Illustration

*a

Front view of wire harness connector

(to Skid Control ECU)
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR (IG1 CIRCUIT)
OK

5.

INSPECT SKID CONTROL ECU (GND1 TERMINAL)

(a) Turn the ignition switch off.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

A4-1 (GND1) - Body ground

Always

Below 1 Ω

Text in Illustration

*a

Front view of wire harness connector

(to Skid Control ECU)
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR (GND1 CIRCUIT)
OK

6.

READ VALUE USING TECHSTREAM (PARKING BRAKE SWITCH)

(a) Reconnect the skid control ECU connector.

(b) Connect the Techstream to the DLC3.

(c) Turn the ignition switch to ON.

(d) Turn the Techstream on.

(e) Enter the following menus: Chassis / ABS/VSC/ TRAC / Data List.

(f) Select the Data List on the Techstream (See page 2016 MY Sienna [12/2015 - 08/2016]; BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: VEHICLE STABILITY CONTROL SYSTEM: DATA LIST / ACTIVE TEST ).

ABS/VSC/TRAC

Tester Display

Measurement Item/Range

Normal Condition

Diagnostic Note

Parking Brake SW

Parking brake switch / ON or OFF

ON: Parking brake applied

OFF: Parking brake released

-

(g) Using the Techstream, check the switch condition on the Techstream changes according to parking brake pedal operation.

OK:

The Techstream displays ON or OFF according to parking brake pedal operation.

NG

GO TO STEP 10

OK

7.

INSPECT BRAKE FLUID LEVEL WARNING SWITCH

(a) Turn the ignition switch off.

(b) Remove the reservoir filler cap and strainer.

(c) Disconnect the brake fluid level warning switch connector.

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

HINT:

A float is located inside the reservoir. Its position can be changed by increasing or decreasing the level of brake fluid.

Standard Resistance:

Tester Connection

Switch Condition

Specified Condition

1 (+) - 2 (E)

Brake fluid level warning switch OFF (Float up)

1.9 to 2.1 kΩ

1 (+) - 2 (E)

Brake fluid level warning switch ON (Float down)

Below 1 Ω

HINT:

If there is no problem after finishing the above check, adjust the brake fluid level to the MAX level.

Text in Illustration

*a

Component without harness connected

(Brake Fluid Level Warning Switch)
NG

REPLACE BRAKE MASTER CYLINDER RESERVOIR ASSEMBLY (BRAKE FLUID LEVEL WARNING SWITCH)

OK

8.

CHECK HARNESS AND CONNECTOR (COMBINATION METER - BRAKE FLUID LEVEL WARNING SWITCH)

(a) Disconnect the combination meter connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

D18-36 (B/LE) - A30-1 (+)

Always

Below 1 Ω

D18-36 (B/LE) - Body ground

Always

10 kΩ or higher

A30-2 (E) - Body ground

Always

Below 1 Ω
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

9.

PERFORM ACTIVE TEST USING TECHSTREAM (BRAKE WARNING LIGHT)

(a) Reconnect the skid control ECU connector.

(b) Connect the Techstream to the DLC3.

(c) Turn the ignition switch to ON.

(d) Turn the Techstream on.

(e) Enter the following menus: Body Electrical / Combination Meter / Active Test.

(f) Select the Active Test on the Techstream.

Combination Meter

Tester Display

Test Part

Control Range

Diagnostic Note

Indicat. Lamp Brake

Brake warning light

OFF or ON

Operate with IG ON and the vehicle is stopped.

(g) Check that the brake warning light on the combination meter turns on or off in accordance with the Techstream operation.

OK:

The brake warning light turns on or off in accordance with the Techstream operation.

HINT:

If troubleshooting has been carried out according to Problem Symptoms Table, refer back to the table and proceed to the next step before replacing the part (See page 2016 MY Sienna [12/2015 - 08/2016]; BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: VEHICLE STABILITY CONTROL SYSTEM: PROBLEM SYMPTOMS TABLE ).

OK

REPLACE BRAKE ACTUATOR ASSEMBLY

NG

REPLACE COMBINATION METER ASSEMBLY

10.

INSPECT PARKING BRAKE SWITCH

(a) Turn the ignition switch off.

(b) Disconnect the parking brake switch connector.

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

Standard Resistance:

Tester Connection

Switch Condition

Specified Condition

1 - Body ground

Parking brake switch ON

(Switch pin free)

Below 1 Ω

1 - Body ground

Parking brake switch OFF

(Switch pin pushed in)

10 kΩ or higher

Text in Illustration

*a

Component without harness connected

(Parking Brake Switch)
NG

REPLACE PARKING BRAKE SWITCH

OK

11.

CHECK HARNESS AND CONNECTOR (INSTRUMENT PANEL JUNCTION BLOCK - PARKING BRAKE SWITCH)

(a) Disconnect the instrument panel junction block assembly connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

2F-16 - A3-1

Always

Below 1 Ω

2F-16 - Body ground

Always

10 kΩ or higher
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

12.

CHECK HARNESS AND CONNECTOR (INSTRUMENT PANEL JUNCTION BLOCK - MAIN BODY ECU)

(a) Remove the main body ECU from the instrument panel junction block assembly.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

2I-12 - 2F-16

Always

Below 1 Ω

2I-12 - Body ground

Always

10 kΩ or higher

HINT:

If troubleshooting has been carried out according to Problem Symptoms Table, refer back to the table and proceed to the next step before replacing the part (See page 2016 MY Sienna [12/2015 - 08/2016]; BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: VEHICLE STABILITY CONTROL SYSTEM: PROBLEM SYMPTOMS TABLE ).

OK

REPLACE MAIN BODY ECU

NG

REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY