Mazda Speed 6. Manual - part 12

04 BRAKES

50

Part name

Function

Normal 
Position

Pressure-
retention solenoid 
valve

Adjusts the fl uid pressure in each brake system according 
to DSC HU/CM signals.

OFF = 
Open

Stability control 
solenoid valve

Switches the brake hydraulic circuits during and according 
to normal braking, ABS and EBD control, TCS control and 
DSC control.

OFF = 
Closed

Brake fl uid 
pressure sensor

Monitors brake fl uid pressure build up to determine hard 
braking to use ABS pump for assist

Not 
applicable

Reservoir

Temporarily stores brake fl uid from the caliper piston to 
ensure smooth pressure reduction during ABS and EBD 
control, TCS control and DSC control.

Not 
applicable

Pressure-
reduction 
solenoid valve

Adjusts the fl uid pressure in each brake system according 
to DSC HU/CM signals.

OFF = 
Closed

Traction switching 
solenoid valve

Switches the brake hydraulic circuits during and according 
to normal braking, ABS and EBD control, TCS control and 
DSC control.

OFF = 
Open

Pump motor

Operates the pump according to DSC HU/CM signals.

Stopped

Pump

Returns the brake fl uid stored in the reservoir to the master 
cylinder during ABS and DSC control. 
Increases brake fl uid pressure and sends brake fl uid to 
each caliper piston during TCS control and DSC control.

Not 
applicable

04 BRAKES

51

Normal Braking 
Fluid pressure passes from the master cylinder through all HU/CM solenoids directly 
to the front and rear brake calipers.

The following happens at the same time:

• 

Right Front Brake Applies 

• 

Left Rear Brake Applies

• 

Right Rear Brake Applies

• 

Left Front Brake Applies

Solenoid Valve Operation Table

Traction 

switching 

solenoid valve

Stability control 

solenoid valve

Pressure-retention 

solenoid valve

Pressure-reduction 

solenoid valve

Pump motor

LF - RR

RF-LR

LF - RR

RF-LR

LF

RF

LR

RR

LF

RF

LR

RR

OFF (Open)

OFF (Closed)

OFF (Open)

OFF (Closed)

Stopped

04 BRAKES

52

ABS/EBD Application

• 

Right Front Pressure Increases

• 

Left Front Pressure Maintains

• 

Both Rear Wheels Pressure Decreases. During pressure reduction, bled-
off pressure is stored in the accumulators

• 

After pressure reduction, the pump returns unused pressure from the 
accumulators back to the brake master cylinder

Traction 

switching 

solenoid 

Stability 

control 

solenoid 

Pressure-retention 

solenoid

Pressure-reduction 

solenoid

Pump 
motor

LF - RR

RF-LR

LF - RR

RF-LR

LF-RF-LR-RR

LF-RF-LR-RR

Pressure 

Increase

OFF 

(Open)

OFF (Closed)

ON (Closed)

OFF (Closed)

Stopped

 Pressure 

Maintain

OFF 

(Open)

OFF (Closed)

ON (Closed)

OFF (Closed)

Stopped

Pressure 

Reduction

OFF 

(Open)

OFF (Closed)

ON (Closed)

ON (Open)

Operating

04 BRAKES

53

DSC: Oversteer Correction

• 

Left turn, the right front wheel is slipping, resulting in oversteer

• 

The pump, traction switching and stability control solenoids are 
energized

• 

Brake pressure is applied to the slipping outer front wheel or slipping 
drive wheel

• 

The inlet solenoid of the inner rear wheel is energized, closing its 
hydraulic circuit

• 

The right front wheel is slowed to correct oversteer 

• 

Additional pressure charges the accumulator/reservoir

Solenoid operation during a left turn to control right front wheel spin

Traction switching 

solenoid 

Stability 

control 

solenoid 

Pressure-retention solenoid 

Pressure-reduction solenoid 

Pump 
motor

LF - RR

RF-LR

LF 

- RR

RF-

LR

LF

RF

LR

RR

LF

RF

LR

RR

 Pressure 

Increase

OFF 

(Open)

ON 

(Closed)

OFF (Closed)

OFF (Closed)

On 

(Closed)

OFF 

(Open)

OFF (Closed)

Operating

Pressure 

Maintain

OFF 

(Open)

ON 

(Closed)

OFF (Closed)

OFF 

(Open)

On (Closed)

OFF 

(Open)

OFF (Closed)

Stopped

Pressure 

Reduction

OFF 

(Open)

ON 

(Closed)

OFF (Closed)

OFF 

(Open)

On (Closed)

OFF 

(Open)

OFF 

(Closed)

On 

(Open)

OFF 

(Closed)

Operating