Technical information
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Technician Guidelines for Antilock Braking Systems
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Seven-Pin Connector An electrical connector used between units of combination
vehicles in North America to conduct electrical power for the
Stop Lamps, Turn Signals, Running Lamps, Ground, and Auxil-
iary (or ABS) circuits. Also known as the SAE J560 connector
Side-by-Side Control A control system that uses one modulator valve on each side of
an axle or axle group to control brake pressures independently,
to improve braking performance on split-co road surfaces.
Six-Channel ABS A system that has six sensors and six modulators (6S/6M).
Skid Number A term representing the coefficient of friction ( µ) of a given
surface as a whole number by multiplying the coefficient of
friction by 100: 0.70µ x 100 = 70 Skid Number.
Software As applied to ABSs, the complete package of programs consist-
ing of the ABS algorithm, error checking diagnostics, engine
management interface, and the structure which links every-
thing together. Software, which is contained in the EPROM(s)
inside the ECU, is a specific set of instructions that the ECU will
execute to perform a particular task.
Solenoid A device that converts an electrical signal into mechanical
movement. It consists of a coil with a moveable core that
changes positions by means of electromagnetism when current
flows through the coil.
Split-Co Split coefficient of friction. A condition in which one side of a
vehicle is on a high coefficient of friction while the other side is
on a low coefficient of friction (e.g., one side of the vehicle on
dry pavement and one side on wet or icy pavement). This
condition is most likely to cause the vehicle to experience yaw
or a twisting/turning action during a stop without an operational
ABS.
Spring Clip See Sensor Bushing.
Static Fault A fault detected with the wheel speed sensors or modulators
when the wheels are not rotating. See Dynamic Fault.
Stop-Lamp Power A design in which the ABS is powered only by the stop lamp
circuit and requires no additional dedicated connector. See Full-
Time Power.