Circuit/System Description

The S45B Liftgate Release Switch has a push button switch to command the liftgate to open and close. The K9 Body Control Module monitors the voltage level on the open/close signal circuit 4652, when the switch is not being pressed the voltage level is at 7.5 volts. When the switch is pressed a contact within the S45B Liftgate Release Switch closes providing a ground path for the signal circuit causing the voltage level to drop to near zero volts. The K9 Body Control Module will detect the voltage drop and will send a serial data message to the K194 Rear Gate Module to command the liftgate to open or close depending upon the current state of the liftgate at the time the switch is pressed.

The S45B Liftgate Release Switch contains 3 resistors which are in series for the liftgate mode, depending upon which position is selected will determine which combination of resistors are used. The K194 Rear Gate Module monitors the voltage level in the Rear Closure Actuation On/Off Switch Signal circuit 4653, as each mode is selected, the voltage within the signal circuit incrementally drops. It is this method the K194 Rear Gate Module will determine if mode switch is in the manual mode, garage mode or the maximum open mode.