Patent attributes
A vehicle locked wheel detector detects initial trailer movement or enablement thereof, for example using a spring brake air pressure switch. The outputs from ABS wheel rotation sensors are monitored to determine whether all wheels are rotating. If one wheel is not rotating, then a locked wheel indicator alerts the driver that one of the wheels may be locked. In some embodiments, if both wheels on one side of the trailer are either stationary or rotating below a threshold speed and the wheels on the opposite side are rotating relatively more quickly, then the trailer is presumed to be pivoting around a sharp turn, and so the wheels will be presumed to be rolling. A finite temporal-spatial interval subsequent to initial trailer movement is defined within which wheel lock can be detected, and upon expiration of the temporal-spatial interval the ABS operates in a normal manner.
