Circuit/System Description
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During power liftgate operation the liftgate module continuously monitors the liftgate position and load profile. The position is calculated from hall effect sensor counts and the electrical load of the gear motor is used to determine physical resistance to the liftgate. The hall effect sensor counts are used to determine when the liftgate has reached the open and closed points of travel where the actuator clutch should be disengaged. These positions may vary slightly and must be learned when most liftgate components are serviced.