Circuit/System Description
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The power liftgate system uses a secondary object detection method which consists of object sensors fixed to both sides of the liftgate near the seal area. The sensors consist of an internal fixed resistor and normally open switch contacts which when closed will bypass the resistor. The sensor signal circuit is supplied 5 volts through a resistor and monitored within the liftgate control module and during normal power liftgate operation the signal circuit should remain a fixed value. When an object presses one of the sensors the contacts close and the resistor is bypassed causing the signal circuit voltage at the module to go low.