The technician’s first step when aligning your car is to inspect for damaged or worn out parts that will prevent proper alignment of thread. Then he measures the car’s current alignment measurement and angles. This is done by mounting an electronic sensor on each of the car’s four wheels. The sensors use infrared beams to measure the position and angle of each wheel and determine exactly in which direction each wheel is pointing. A car severely out of alignment may have all four wheels pointing in different directions.
As the technician steers the wheels to various positions for a complete set of alignment measurements the sensors send the information to the aligner’s computer console. The computer compares your car’s current alignment measurement to the manufacturer’s (O.E.M.) specification in its database. The aligner then provides the technician with the exact information he needs to adjust your car’s alignment to match factory specification.