СИСТЕМА ECD Brake Override System

DESCRIPTION

When the vehicle is being driven, depressing the accelerator pedal sensor assembly and brake pedal will activate the brake override system to restrict driving torque. The conditions for activating the brake override system as well as the items that are controlled are explained below.

Activation Conditions:
- Vehicle is running at or above the specified speed.
- When the accelerator pedal and brake pedal are depressed.
Note

The vehicle may not enter the brake override system control due to the relation of the accelerator pedal angle and the vehicle's speed.

Items Controlled:
- Driving torque is restricted.
Tech Tips

During brake override system control, the value for the accelerator pedal angle (which is used for engine control) is forcibly reduced to a specified value. For this reason, the Data List value for Accelerator Position will be replaced with a specified value regardless of the actual accelerator pedal angle (Accel Sens. No. 1 Volt %, Accel Sens. No. 2 Volt %)

Deactivation Conditions:
- When the brake pedal or the accelerator pedal returns to some degree.

CAUTION / NOTICE / HINT

Inspection Method
Drive at 10 km/h (6.25 mph), depress the accelerator pedal by 1/2 to 3/4 and keep it in that position. Under these conditions, if the engine speed decreases to 1000 rpm when the brake pedal is depressed, then the brake override system has been activated.

CAUTION:

When carrying out the inspection, use a place where you are able to carry it out safely and also pay close attention to your surroundings.

Also, when driving, make absolutely sure that all road traffic laws, such as speed limits, are observed.

Tech Tips

Under normal conditions, the Accelerator Position value changes in response to the Accel Sens. No. 1 Volt % value. For more information on the numerical values, refer to the Data List Click here.
If the Data List values of Accelerator Position and Accel Sens. No. 1 Volt % do not match, and the value of Accelerator Position changes but the value of Accel Sens. No. 1 Volt % is constant, this confirms that brake override system has activated. (Data can be captured relatively easily by using the snapshot function in the Data List. Confirm the data after performing the drive test.)

Note

The brake override system restricts driving torque if the brake pedal is depressed when driving with the accelerator pedal depressed. If a customer reports experiencing loss of torque after the accelerator and brake pedals have both been intentionally depressed, explain to the customer that this is not a malfunction, and that the customer should avoid depressing both the accelerator and brake pedals at the same time.

Example: While operating the accelerator pedal, the customer uses their left foot to operate the brake pedal.

PROCEDURE

CHECK DTC OUTPUT

Connect the GTS to the DLC3.
Turn the ignition switch to ON and turn the GTS on.
Enter the following menus: Utility / All Codes.

Check DTCs.

Result

Proceed to
No DTC is output
DTC is output

DTC is output

GO TO DTC CHART Click here

No DTC is output

READ VALUE USING GTS (MASTER CYLINDER SENSOR)

Connect the GTS to the DLC3.
Turn the ignition switch to ON and turn the GTS on.
Enter the following menus: Chassis / ABS/VSC/TRC / Data List / Master Cylinder Sensor.

Chassis > ABS/VSC/TRC > Data List

Tester Display

Master Cylinder Sensor

Tester Display
Master Cylinder Sensor

Read the value displayed on the GTS.

GTS Display	Measurement Item/Range	Normal Condition
Master Cylinder Sensor	Master cylinder pressure sensor reading/ Min.: 0.00 V, Max.: 5.00 V	Brake pedal released: 0.30 to 0.90 V Reading increases when brake pedal is depressed

GTS Display

Measurement Item/Range

Normal Condition

Master Cylinder Sensor

Master cylinder pressure sensor reading/

Min.: 0.00 V, Max.: 5.00 V

Brake pedal released: 0.30 to 0.90 V
Reading increases when brake pedal is depressed

Check that the brake fluid pressure value of the "Maser Cylinder Sensor" observed on the GTS changes when the brake pedal is depressed.

OK
When the pedal is depressed, the voltage displayed on the GTS increases.

Result

Proceed to
OK
NG

CHECK BRAKE ACTUATOR ASSEMBLY

READ VALUE USING GTS (STOP LIGHT SWITCH)

Connect the GTS to the DLC3.
Turn the ignition switch to ON and turn the GTS on.
Enter the following menus: Powertrain / Engine / Data List / Stop Light Switch.

Powertrain > Engine > Data List

Tester Display

Stop Light Switch

Tester Display
Stop Light Switch

Check the Data List indication when the brake pedal is depressed and released.

Tester Display	Condition	Specified Condition
Stop Light Switch	Brake pedal released	OFF
Stop Light Switch	Brake pedal depressed	ON

Result

Proceed to
OK
NG

INSPECT STOP LIGHT SWITCH ASSEMBLY Click here

INSPECT BRAKE PEDAL

Inspect and adjust the brake pedal.

Click here

Tech Tips

If the stop light switch turns ON too late, the start of brake override system control may be delayed; if it turns ON too soon, brake override system control may begin too early, so conduct inspection of the brake pedal and stop light switch assembly.

Result

Proceed to
OK
NG

REPAIR OR REPLACE BRAKE PEDAL Click here

READ VALUE USING GTS (ACCELERATOR PEDAL POSITION SENSOR)

Connect the GTS to the DLC3.
Turn the ignition switch to ON and turn the GTS on.

Enter the following menus: Powertrain / Engine / Data List / Accel Sens. No. 1 Volt % and Accel Sens. No. 2 Volt %.

Powertrain > Engine > Data List

Tester Display
Accel Sens. No.1 Volt %
Accel Sens. No.2 Volt %

Read the value displayed on the tester.

Tester Display

Condition

Specified Condition

Accel Sens. No. 1 Volt %

Accelerator Pedal

Released → Depressed → Released

Values smoothly change following accelerator pedal operation

Accel Sens. No. 2 Volt %

Tech Tips

For numerical values of Accel Sens. No. 1 Volt % and Accel Sens. No. 2 Volt %, refer to the Data List (See page XX-XX).

Result

Proceed to
OK
NG

REPLACE ACCELERATOR PEDAL SENSOR ASSEMBLY Click here

READ VALUE USING GTS (VEHICLE SPEED)

Connect the GTS to the DLC3.
Turn the ignition switch to ON and turn the GTS on.
Start the engine.
Enter the following menus: Powertrain / Engine / Data List / Vehicle Speed.

Powertrain > Engine > Data List

Tester Display

Vehicle Speed

Tester Display
Vehicle Speed

Read the value displayed on the tester.

Standard

Tester Display	Condition	Specified Condition
Vehicle Speed	Vehicle stopped, engine running	0 km/h (0 mph)
Vehicle Speed	Vehicle running at constant speed between 16.1 to 64.4 km/h (10 to 40 mph)	No large fluctuations when driving at a constant speed

CAUTION:

When performing the confirmation driving pattern, obey all speed limits and traffic laws.

Tech Tips

Data can be captured relatively easily by using the snapshot function in the Data List. Confirm the data after performing the drive test.

Result

Proceed to
OK
NG

GO TO METER / GAUGE SYSTEM (SPEED SIGNAL CIRCUIT) Click here

READ VALUE USING GTS (FR, FL, RR, RL WHEEL SPEED)

Connect the GTS to the DLC3.
Turn the ignition switch to ON and turn the GTS on.
Start the engine.

Enter the following menus: Chassis / ABS/VSC/TRC / Data List / FR Wheel Speed, FL Wheel Speed, RR Wheel Speed and RL Wheel Speed.

Chassis > ABS/VSC/TRC > Data List

Tester Display
FR Wheel Speed
FL Wheel Speed
RR Wheel Speed
RL Wheel Speed

Read the value displayed on the tester.

Standard

Tester Display

Condition

Specified Condition

FR Wheel Speed

FL Wheel Speed

RR Wheel Speed

RL Wheel Speed

Vehicle stopped, engine running

0 km/h (0 mph)

Vehicle running at constant speed between 16.1 to 64.4 km/h (10 to 40 mph)

No large fluctuations when driving at a constant speed

CAUTION:

When performing the confirmation driving pattern, obey all speed limits and traffic laws.

Tech Tips

Data can be captured relatively easily by using the snapshot function in the Data List. Confirm the data after performing the drive test.

Result

Proceed to
OK
NG

END

INSPECT FRONT OR REAR SPEED SENSOR