BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: ELECTRONICALLY CONTROLLED BRAKE SYSTEM (for Gasoline Model): TEST MODE PROCEDURE; 2021 MY Avalon [08/2020

Last Modified: 08-21-2023	6.11:8.1.0	Doc ID: RM100000001Q21B
Model Year Start: 2021	Model: Avalon	Prod Date Range: [08/2020 - 08/2021]
Title: BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: ELECTRONICALLY CONTROLLED BRAKE SYSTEM (for Gasoline Model): TEST MODE PROCEDURE; 2021 MY Avalon [08/2020 - 08/2021]

TEST MODE PROCEDURE

WARNING LIGHT AND INDICATOR LIGHT INITIAL CHECK

(a) When the engine switch is turned on (IG), check that the ABS warning light, brake system warning light (red indicator), VSC OFF indicator light, brake hold standby indicator light, brake hold operated indicator light and slip indicator light come on for approximately 3 seconds.

HINT:

When the brake fluid level is low or the vacuum inside the brake booster decreases, the brake system warning light (red indicator) comes on.
If the skid control ECU (brake actuator assembly) stores a DTC, the ABS warning light, brake system warning light (red indicator) and slip indicator lights will come on.
If a DTC is stored by the skid control ECU (brake actuator assembly) and the following conditions are met when the brake hold switch (electric parking brake switch assembly) is pressed, the brake hold operated indicator light blinks.
- Vehicle Conditions:
  1. The driver door is closed.
  2. The driver seat belt is fastened.
If any of the indicators remains on or does 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 system warning light (red indicator) circuit (Remains on)
Brake system warning light (red indicator) 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)
Brake hold standby indicator light circuit
Brake hold operated indicator light circuit

SENSOR CHECK USING TEST MODE (SIGNAL CHECK) (When Using TECHSTREAM)

NOTICE:

Perform Test Mode (Signal Check) with the vehicle stopped.

HINT:

DTCs are stored if any malfunctions are detected during the check of each sensor.
When entering Test Mode (Signal Check), the skid control ECU (brake actuator assembly) communicates with the driving support ECU assembly to judge whether the vehicle is equipped with the pre-collision system. Therefore, do not exit Test Mode (Signal Check) within 5 seconds of entering Test Mode (Signal Check).

(a) Procedure to enter Test Mode (Signal Check)

(1) Turn the engine switch off.

(2) Check that the steering wheel is centered.

(3) Check that the shift lever is in P.

(4) Connect the Techstream to the DLC3.

(5) Turn the engine switch on (IG).

(6) Turn the Techstream on.

(7) Switch the skid control ECU (brake actuator assembly) to Test Mode (Signal Check) using the Techstream. Enter the following menus: Chassis / ABS/VSC/TRAC/EPB / Utility / Signal Check.

Chassis > ABS/VSC/TRAC/EPB > Utility

Tester Display
Signal Check

HINT:

Do not exit Test Mode (Signal Check) within 5 seconds of entering Test Mode (Signal Check). If Test Mode (Signal Check) is exited within 5 seconds of entering Test Mode (Signal Check), DTC U1104 may be stored. If DTC U1104 is output after exiting Test Mode (Signal Check), enter Test Mode (Signal Check) again, wait at least 5 seconds, then recheck for DTCs.

(8) Check that the ABS warning and slip indicator lights come on for several seconds and the ABS warning, slip indicator and parking brake indicator lights blink in the Test Mode pattern.

HINT:

If the ABS warning, slip indicator and parking brake indicator lights do not blink, inspect the ABS warning, slip indicator and parking brake indicator light circuits.
While the parking brake is engaged, the parking brake indicator light illuminates but does not blink in the Test Mode pattern.

(9) Check the ABS sensors.

HINT:

Check that the ABS warning light is blinking in the Test Mode pattern before performing the following ABS sensor checks.

(b) Speed Sensor Check

(1) Drive the vehicle straight-ahead.

Accelerate the vehicle to a speed of 47 to 55 km/h (29 to 34 mph) for several seconds.

NOTICE:

If the vehicle is driven at 80 km/h or more after the ABS warning light turns off, the speed sensor check will be performed again. In this situation, the ABS warning light will start blinking again.

HINT:

The speed sensor check may not complete if wheelspin occurs.
The speed sensor check may not complete if the speed sensor check is started while turning the steering wheel.

(2) Check that the ABS warning light goes off.

HINT:

The ABS warning light goes off when the sensor check has completed.
The ABS warning light comes on immediately after a malfunction has been detected during the speed sensor check.

(3) Stop the vehicle.

NOTICE:

If the sensor check has not completed, the ABS warning light will blink while the vehicle is being driven and the ABS will not operate.

HINT:

When the sensor check has completed, the ABS warning light goes off while the vehicle is being driven, and blinks in the Test Mode pattern while the vehicle is stopped.

(1) Press the VSC OFF switch.

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

(3) Press the VSC OFF switch again.

(d) Brake Hold Switch (Electric Parking Brake Switch Assembly) Check

(1) Make sure the following conditions are met:

The driver door is closed.
The driver seat belt is fastened.

(2) Press the brake hold switch (electric parking brake switch assembly).

(3) Check that the brake hold standby indicator light comes on.

(4) Press the brake hold switch (electric parking brake switch assembly) again.

(e) End of Sensor Check

(1) If the sensor checks have completed, the ABS warning light blinks in the Test Mode pattern when the vehicle is stopped and the ABS warning light goes off while the vehicle is being driven.

NOTICE:

If the sensor checks have not completed, the ABS warning light will blink while the vehicle is being driven and the ABS will not operate.

(f) End of Test Mode (Signal Check)

(1) Turn the engine switch off and disconnect the Techstream.

(g) 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 wire harness Improperly connected connector, deformation or corrosion of terminals Sensor installation Front speed sensor rotor RH (front axle hub sub-assembly RH)
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 wire harness Improperly connected connector, deformation or corrosion of terminals Sensor installation Front speed sensor rotor LH (front axle hub sub-assembly LH)
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 wire harness Improperly connected connector, deformation or corrosion of terminals Sensor installation Rear speed sensor rotor RH (rear axle hub and bearing assembly RH)
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 wire harness Improperly connected connector, deformation or corrosion of terminals Sensor installation Rear speed sensor rotor LH (rear axle hub and bearing assembly LH)
Change in Output Signal of Front Speed Sensor RH	Incomplete/complete	Check the stability of the sensor output waveform	Front speed sensor RH Front speed sensor rotor RH (front axle hub sub-assembly RH)
Change in Output Signal of Front Speed Sensor LH	Incomplete/complete	Check the stability of the sensor output waveform	Front speed sensor LH Front speed sensor rotor LH (front axle hub sub-assembly LH)
Change in Output Signal of Rear Speed Sensor RH	Incomplete/complete	Check the stability of the sensor output waveform	Rear speed sensor RH1 Rear speed sensor RH (rear axle hub and bearing assembly RH)2 Rear speed sensor rotor RH (rear axle hub and bearing assembly RH)
Change in Output Signal of Rear Speed Sensor LH	Incomplete/complete	Check the stability of the sensor output waveform	Rear speed sensor LH1 Rear speed sensor LH (rear axle hub and bearing assembly LH)2 Rear speed sensor rotor LH (rear axle hub and bearing assembly LH)

*1: for AWD
*2: for 2WD