BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: VEHICLE STABILITY CONTROL SYSTEM: TEST MODE PROCEDURE; 2018 - 2020 MY Sienna [11/2017

Last Modified: 04-05-2023	6.11:8.1.0	Doc ID: RM1000000018KDX
Model Year Start: 2018	Model: Sienna	Prod Date Range: [11/2017 - ]
Title: BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: VEHICLE STABILITY CONTROL SYSTEM: TEST MODE PROCEDURE; 2018 - 2020 MY Sienna [11/2017 - ]

TEST MODE PROCEDURE

1. WARNING LIGHT AND INDICATOR LIGHT INITIAL CHECK

(a) When the ignition switch turned to ON, check that the ABS warning, brake warning, VSC OFF indicator and slip indicator lights all come on for approximately 3 seconds.

HINT:

When the brake fluid level is low, the brake warning light comes on.
If the skid control ECU (brake actuator assembly) stores any DTCs, the ABS warning and slip indicator lights will come on.
If any of the indicators remain on or do not come on, proceed to troubleshooting for the light circuits listed below.

Trouble Area	See Procedure
ABS warning light circuit (Remains on)
ABS warning light circuit (Does not come on)
Brake warning light circuit (Remains on)
Brake warning light circuit (Does not come on)
VSC OFF indicator light circuit (Remains on)
VSC OFF indicator light circuit (Does not come on)
Slip indicator light circuit (Remains on)
Slip indicator light circuit (Does not come on)

2. SENSOR CHECK USING TEST MODE (SIGNAL CHECK) (When Using Techstream)

HINT:

VSC does not operate in Test Mode (signal check), regardless of whether the sensor check is normal or abnormal.
When a malfunction occurs in an ABS system sensor, the ABS warning light illuminates.
When a malfunction occurs in a VSC system sensor, the slip indicator light illuminates.

(a) Procedure to enter Test Mode (signal check).

(1) Turn the ignition switch to ON.

(2) Make sure the shift lever is in P.

(3) Apply the parking brake.

(4) Put the steering wheel in the neutral position.

(5) Turn the ignition switch off and connect the Techstream to the DLC3.

(6) Turn the ignition switch to ON and turn the Techstream on.

(7) Enter the following menus: Chassis / ABS/VSC/TRAC / Utility / Signal Check.

HINT:

Signals related to the VSC system can be inspected by performing a Test Mode (signal check) inspection. During the inspection, the display of items determined normal by the skid control ECU (brake actuator assembly) changes from incomplete to complete.

(b) Acceleration Sensor Check

(1) Enter Test Mode (signal check).

(2) Keep the vehicle stationary on a level surface for 1 second or more.

HINT:

The acceleration sensor check can be performed with the master cylinder pressure sensor check below.

(1) Depress the brake pedal several times to release vacuum from the brake booster assembly with the engine stopped.

(2) Turn the ignition switch to ON.

(3) Check that the brake warning light comes on when depressing the brake pedal with a force of 59.0 N (6.0 kgf, 13.2 lbf) or more for 1 second or more. (The lost booster pressure state is judged to be normal.)

(4) Start the engine while depressing the brake pedal with a force of 59.0 N (6.0 kgf, 13.2 lbf) or more for 1 second or more.

(5) Check that the brake warning light goes off when quickly releasing the brake pedal. (The lost booster pressure state is judged to be normal.)

(6) Leave the vehicle for 1 second or more. (Master cylinder pressure sensor zero point calibration)

NOTICE:

If the brake pedal is depressed slowly or repeatedly, the master cylinder pressure sensor zero point calibration will not complete normally.
If the lost booster pressure judgment check results are not normal, then the master cylinder pressure sensor check cannot be performed.
If rechecking after the engine has started, end Test Mode, enter Test Mode again, and release vacuum in the booster by pumping the brake pedal prior to rechecking.

HINT:

If the lost booster pressure state is not judged to be normal, the brake warning light comes on and Test Mode (signal check) inspection item (Output Master Cylinder Pressure Sensor) is displayed.

(d) Master Cylinder Pressure Sensor Check

(1) Enter Test Mode (signal check).

(2) Start the engine.

(3) Leave the vehicle in a stationary condition and release the brake pedal for 1 second or more, and quickly and continuously depress the brake pedal with a force greater than 98 N (10 kgf, 22.0 lbf) for 1 second.

(4) Check that the ABS warning light stays on for 3 seconds.

HINT:

Ensure that the ABS warning light comes on.
While the ABS warning light stays on, continue to depress the brake pedal with a force of 98 N (10 kgf, 22 lbf) or more.
The ABS warning light comes on for 3 seconds every time the brake pedal operation above is performed.
If the master cylinder pressure sensor check is not completed, depressing the brake pedal causes further decreases in vacuum in the brake booster, making the sensor check difficult to complete.
If the vacuum is insufficient, the master cylinder pressure sensor check may not be completed. In this case, run the engine at idle to obtain sufficient vacuum.
If the brake pedal is strongly depressed when the vacuum is insufficient, the brake warning light may come on in accordance with booster pressure control. In this case, run the engine at idle to obtain sufficient vacuum.

(e) Speed Sensor Check

NOTICE:

Before performing the speed sensor signal check, complete the acceleration sensor and master cylinder pressure sensor checks.

(1) Enter Test Mode (signal check).

(2) Start the engine.

(3) Drive the vehicle straight ahead.

Accelerate the vehicle to a speed of 45 km/h (28 mph) or more for several seconds and check that the ABS warning light goes off.

The sensor check may not complete if wheelspin occurs.
The ABS warning light blinks when the sensor check has been completed and the brake pedal is depressed.
The ABS warning light comes on immediately after a malfunction has been detected during the speed sensor check.

(4) Stop the vehicle.

NOTICE:

The speed sensor check may not complete if the sensor check is started with the steering wheel turned or one or more wheels spinning.
After the ABS warning light goes off and if the vehicle speed exceeds 80 km/h (50 mph), a sensor check code will be stored again. Decelerate or stop the vehicle before the speed reaches 80 km/h (50 mph).
If the sensor check has not been completed, the ABS warning light blinks during driving and the ABS system does not operate.

HINT:

When the sensor check has been completed, the ABS warning light remains off during driving and blinks in the Test Mode (signal check) pattern while the vehicle is stationary.

(f) VSC Sensor Check

HINT:

Check that the slip indicator light is blinking in the Test Mode pattern before performing the following VSC sensor check.

(g) VSC OFF Switch Check

(1) Press the VSC OFF switch.

(2) Check that the VSC OFF indicator light comes on.

(3) Press the VSC OFF switch again.

(h) End of Sensor Check

(1) If the sensor check is completed, the ABS warning light and slip indicator light blink (Test Mode (signal check)) when the vehicle stops and the ABS warning light is off while the vehicle is being driven.

NOTICE:

When Test Mode (signal check) is started with the Techstream and all items display complete, the sensor check ends.
If the sensor check is not complete, the ABS warning light blinks when the vehicle is in motion and the ABS does not operate.
If a DTC is detected in Test Mode (signal check), the ABS warning light or slip indicator light illuminates.

(i) End of Test Mode (Signal Check)

(1) End Test Mode (signal check) using the Techstream.

Turn the ignition switch off and enter normal mode.
Remove the Techstream.

(j) Test Mode (Signal Check) Inspection Item Chart

Item Name	Range	Judgment Description	Trouble Area
Output Signal of Front Speed Sensor RH	Incomplete/complete	Check for foreign matter, check the gap between the sensor and rotor	Open or short in speed sensor Open or short in sensor system wire harness Defective connector contact or increased terminal resistance Speed sensor installation defect Sensor rotor system malfunction
Output Signal of Front Speed Sensor LH	Incomplete/complete	Check for foreign matter, check the gap between the sensor and rotor	Open or short in speed sensor Open or short in sensor system wire harness Defective connector contact or increased terminal resistance Speed sensor installation defect Sensor rotor system malfunction
Output Signal of Rear Speed Sensor RH	Incomplete/complete	Check for foreign matter, check the gap between the sensor and rotor	Open or short in speed sensor Open or short in sensor system wire harness Defective connector contact or increased terminal resistance Speed sensor installation defect Sensor rotor system malfunction
Output Signal of Rear Speed Sensor LH	Incomplete/complete	Check for foreign matter, check the gap between the sensor and rotor	Open or short in speed sensor Open or short in sensor system wire harness Defective connector contact or increased terminal resistance Speed sensor installation defect Sensor rotor system malfunction
Change in Output Signal of Front Speed Sensor RH	Incomplete/complete	Check the stability of the sensor input waveform Check the straight ahead signal inputs	Foreign object attached to speed sensor Sensor rotor system malfunction
Change in Output Signal of Front Speed Sensor LH	Incomplete/complete	Check the stability of the sensor input waveform Check the straight ahead signal inputs	Foreign object attached to speed sensor Sensor rotor system malfunction
Change in Output Signal of Rear Speed Sensor RH	Incomplete/complete	Check the stability of the sensor input waveform Check the straight ahead signal inputs	Foreign object attached to speed sensor Sensor rotor system malfunction
Change in Output Signal of Rear Speed Sensor LH	Incomplete/complete	Check the stability of the sensor input waveform Check the straight ahead signal inputs	Foreign object attached to speed sensor Sensor rotor system malfunction
Output Voltage Deceleration Sensor	Incomplete/complete	Check the acceleration sensor output voltage	Acceleration sensor zero point stored incorrectly Acceleration sensor (airbag sensor assembly) connector connection malfunction Acceleration sensor (airbag sensor assembly) internally stuck Defective acceleration sensor (airbag sensor assembly) installation
Memory System Information	Incomplete/complete	Check stored system information (skid control ECU (brake actuator assembly)) against vehicle specification	ECM incorrectly installed Brake actuator assembly incorrectly installed CAN communication between ECM and skid control ECU (brake actuator assembly)
Output Master Cylinder Pressure Sensor	Incomplete/complete	Check the master cylinder pressure sensor zero point voltage Check that the sensitivity of the master cylinder pressure sensor is normal	Open circuit or short in master cylinder pressure sensor circuit Open or short in stop light switch assembly circuit or defective connector connection Stop light switch assembly stuck OFF
Judgment of Failure State	Incomplete/complete	Check that the brake pedal load sensing switch is normal	Open or short in brake pedal load sensing switch system wire harness Brake pedal load sensing switch stuck ON/OFF

3. SENSOR CHECK USING TEST MODE (SIGNAL CHECK) (When not Using Techstream)

HINT:

VSC does not operate in Test Mode (signal check), regardless of whether the sensor check is normal or abnormal.
When a malfunction occurs in an ABS system sensor, the ABS warning light illuminates.
When a malfunction occurs in a VSC system sensor, the slip indicator light illuminates.

(a) Procedure to enter Test Mode (signal check).

(1) Turn the ignition switch to ON.

(2) Make sure the shift lever is in P.

(3) Apply the parking brake.

(4) Put the steering wheel in the neutral position.

Text in Illustration

*a	Front view of DLC3

(5) Turn the ignition switch off.

(6) Using SST, connect terminals 12 (TS) and 4 (CG) of the DLC3.

SST: 09843-18040

(7) Turn the ignition switch to ON.

(8) Check that the ABS warning and slip indicator lights come on for several seconds and then blink in Test Mode (signal check).

HINT:

If the ABS warning and slip indicator lights do not blink, inspect the TS and CG terminal circuit and ABS warning and slip indicator light circuits.

Trouble Area	See Procedure
TS and CG terminal circuit
ABS warning light circuit (Remains on)
ABS warning light circuit (Does not come on)
Slip indicator light circuit (Remains on)
Slip indicator light circuit (Does not come on)

4. ACCELERATION SENSOR CHECK

(a) Enter Test Mode (signal check).

(b) Keep the vehicle stationary on a level surface for 1 second or more.

HINT:

The acceleration sensor check can be performed with the master cylinder pressure sensor check below.

(1) Depress the brake pedal several times to release vacuum from the brake booster assembly with the engine stopped.

(2) Turn the ignition switch to ON.

(4) Start the engine while depressing the brake pedal with a force of 59.0 N (6.0 kgf, 13.2 lbf) or more for 1 second or more.

(5) Check that the brake warning light goes off when quickly releasing the brake pedal. (The lost booster pressure state is judged to be normal.)

(6) Leave the vehicle for 1 second or more. (Master cylinder pressure sensor zero point calibration)

NOTICE:

If the brake pedal is depressed slowly or repeatedly, the master cylinder pressure sensor zero point calibration will not complete normally.
If the lost booster pressure judgment check results are not normal, then the master cylinder pressure sensor check cannot be performed.
If rechecking after the engine has started, end Test Mode, enter Test Mode again, and release vacuum in the booster by pumping the brake pedal prior to rechecking.

HINT:

If the lost booster pressure state is not judged to be normal, the brake warning light comes on and Test Mode (signal check) inspection item (Output Master Cylinder Pressure Sensor) is displayed.

5. MASTER CYLINDER PRESSURE SENSOR CHECK

(a) Enter Test Mode (signal check).

(b) Start the engine.

(c) Leave the vehicle in a stationary condition and release the brake pedal for 1 second or more, and quickly and continuously depress the brake pedal with a force of 98 N (10 kgf, 22 lbf) or more for 1 second.

(d) Check that the ABS warning light stays on for 3 seconds.

HINT:

Ensure that the ABS warning light comes on.
While the ABS warning light stays on, continue to depress the brake pedal with a force of 98 N (10 kgf, 22 lbf) or more.
The ABS warning light comes on for 3 seconds every time the brake pedal operation above is performed.
If the master cylinder pressure sensor check is not completed, depressing the brake pedal causes further decreases in vacuum in the brake booster, making the sensor check difficult to complete.
If the vacuum is insufficient, the master cylinder pressure sensor check may not be completed. In this case, run the engine at idle to obtain sufficient vacuum.
If the brake pedal is strongly depressed when the vacuum is insufficient, the brake system warning light (red indicator) may come on in accordance with booster pressure control. In this case, run the engine at idle to obtain sufficient vacuum.

6. SPEED SENSOR CHECK

NOTICE:

Before performing the speed sensor signal check, complete the acceleration sensor and master cylinder pressure sensor checks.

(a) Enter Test Mode (signal check).

(b) Start the engine.

Accelerate the vehicle to a speed of 45 km/h (28 mph) or more for several seconds and check that the ABS warning light goes off.

The sensor check may not be completed if wheelspin occurs.
The ABS warning light blinks when the sensor check has been completed and the brake pedal is depressed.
The ABS warning light comes on immediately after a malfunction has been detected during the speed sensor check.

(d) Stop the vehicle.

NOTICE:

The speed sensor check may not be completed if the sensor check is started with the steering wheel turned or one or more wheels spinning.
After the ABS warning light goes off and if the vehicle speed exceeds 80 km/h (50 mph), a sensor check code will be stored again. Decelerate or stop the vehicle before the speed reaches 80 km/h (50 mph).
If the sensor check has not been completed, the ABS warning light blinks during driving and the ABS system does not operate.

HINT:

When the sensor check has been completed, the ABS warning light remains off during driving and blinks in the Test Mode (signal check) pattern while the vehicle is stationary.

(e) VSC Sensor Check

HINT:

Check that the slip indicator light is blinking in the Test Mode pattern before performing the following VSC sensor check.

(f) VSC OFF Switch Check

(1) Press the VSC OFF switch.

(2) Check that the VSC OFF indicator light comes on.

(3) Press the VSC OFF switch again.

7. END OF SENSOR CHECK

(a) If the sensor check is completed, the ABS warning light and slip indicator light blink (Test Mode (signal check)) when the vehicle stops and the ABS warning light is off while the vehicle is being driven.

NOTICE:

When Test Mode (signal check) is started with the Techstream and all items display complete, the sensor check ends.
If the sensor check is not complete, the ABS warning light blinks when the vehicle is in motion and the ABS does not operate.
If a DTC is detected in Test Mode (signal check), the ABS warning light or slip indicator light illuminates.

8. END OF TEST MODE (SIGNAL CHECK)

(a) End Test Mode (signal check) using the Techstream.

Turn the ignition switch off and enter normal mode.
Remove the Techstream.

(b) End Test Mode (signal check) by connecting DLC3 terminals.

Turn the ignition switch off and disconnect terminals 13 (TC), 12 (TS) and 4 (CG) of the DLC3.
Turn the ignition switch to ON.
HINT:
- Test Mode (signal check) is continued if 12 (TS) and 4 (CG) are disconnected while the ignition switch is ON.
- If the ignition switch turned to ON with terminals 12 (TS) and 4 (CG) connected, the previous Test Mode (signal check) is maintained.