Gear Motor Assembly

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The liftgate motor is a bi-directional motor and open or close operation is the result of the direction of the motor rotation. The liftgate module controls the liftgate motor through the control circuits by suppling power and ground in the appropriate polarity. The motor control circuits are monitored by the liftgate module prior to activation for a high or low condition and during motor operation for any irregular current flow conditions.

The liftgate motor clutch engages or disengages the liftgate motor to the liftgate drive gear and is the component that determines power or manual operation. When the liftgate module supplies power to the clutch control circuit the clutch coil is energized and the liftgate motor is engaged to the liftgate drive gear so that power operation can occur. The liftgate module monitors the clutch control circuit at all times for a short high while in an inactive state or a short low or insufficient current flow while in an active state.

The full open switch is part of the gear motor assembly and will close and become active when the liftgate reaches the full open position. The full open switch signal circuit is supplied battery voltage through a resistor and monitored within the liftgate module. The liftgate provides a low reference circuit and when the switch contacts close the signal circuit goes low and the liftgate module determines the switch to be active.