A method of adjusting test braking pulses during stability control of a vehicle (10) including the steps of: applying a first test braking pulse to at least one wheel of the vehicle (10), the application of the test braking pulse comprising operating a brake actuator (112) to apply a low level braking pressure of the wheel, determining a first longitudinal acceleration (A.sub.Long1) of the vehicle (10) during the test braking pulse, obtaining a second longitudinal acceleration (A.sub.Long2) indicative of the longitudinal acceleration of the vehicle (10) when a test braking pulse is not being applied, calculating a change in longitudinal acceleration during the test braking pulse, and determining whether the change in longitudinal acceleration is acceptable, and if not, adjusting the level of the braking pressure applied in a subsequent test braking pulse.

One embodiment provides a vehicle brake hydraulic controller including: an antilock braking controlling module configured to perform an antilock braking control in which a brake hydraulic pressure applied to wheel brakes is reduced under the condition that a slip-related amount has reached a pressure reduction threshold value; and a turning judging module configured to judge whether a vehicle is turning based on a steering angle, wherein, when the antilock braking control is performed and in the case that the turning judging module judges that the vehicle is turning, the antilock braking controlling module performs a turning pressure reduction control so as to: change the pressure reduction threshold values to be more easily reached by the slip-related amount than at the time of straight running; and change the pressure reduction amounts to be larger than that at the time of straight running.

One embodiment provides a vehicle brake hydraulic controller including: an antilock braking controlling module configured to perform an antilock braking control in which a brake hydraulic pressure applied to wheel brakes is reduced under the condition that a slip-related amount has reached a pressure reduction threshold value; and a turning judging module configured to judge whether a vehicle is turning based on a steering angle, wherein, when the antilock braking control is performed and in the case that the turning judging module judges that the vehicle is turning, the antilock braking controlling module performs a turning pressure reduction control so as to: change the pressure reduction threshold values to be more easily reached by the slip-related amount than at the time of straight running; and change the pressure reduction amounts to be larger than that at the time of straight running.

One embodiment provides a vehicle brake hydraulic controller including: an antilock braking controlling module configured to perform an antilock braking control in which a brake hydraulic pressure applied to wheel brakes is reduced under the condition that a slip-related amount has reached a pressure reduction threshold value; and a turning judging module configured to judge whether a vehicle is turning based on a steering angle, wherein, when the antilock braking control is performed and in the case that the turning judging module judges that the vehicle is turning, the antilock braking controlling module performs a turning pressure reduction control so as to: change the pressure reduction threshold values to be more easily reached by the slip-related amount than at the time of straight running; and change the pressure reduction amounts to be larger than that at the time of straight running.

A method of adjusting test braking pulses during stability control of a vehicle (10) including the steps of: applying a first test braking pulse to at least one wheel of the vehicle (10), the application of the test braking pulse comprising operating a brake actuator (112) to apply a low level braking pressure of the wheel, determining a first longitudinal acceleration (A.sub.Long1) of the vehicle (10) during the test braking pulse, obtaining a second longitudinal acceleration (A.sub.Long2) indicative of the longitudinal acceleration of the vehicle (10) when a test braking pulse is not being applied, calculating a change in longitudinal acceleration during the test braking pulse, and determining whether the change in longitudinal acceleration is acceptable, and if not, adjusting the level of the braking pressure applied in a subsequent test braking pulse.