Windows and Glass: Description and Operation
The windshield glass:
^ Is standard plastic and glass laminate safety glass.
^ Is bonded to the window opening flange with urethane sealant.
The liftgate window glass:
^ Is standard plastic and glass laminate safety glass.
^ Houses the rear defogger grid.
The front door window glass:
^ Is standard plastic and glass laminate safety glass.
^ May be raised and lowered by use of the window regulator handle (standard).
^ May be raised and lowered by use of the window regulator control switch (optional).
The rear door window glass:
^ Is standard plastic and glass laminate safety glass.
^ May be raised and lowered by use of the window regulator handle (standard).
^ May be raised and lowered by use of the window regulator control switch (optional).
The quarter window glass:
^ Is standard plastic and glass laminate safety glass.
Glass, Frames and Mechanisms - Window Regulator Control
The window regulator control switch:
^ Is located on each door trim panel.
^ May be used to raise or lower both LH side and RH side windows from the master control on the driver door.
^ Includes a window lock feature that is controlled through the master control.
^ Can manually lower the driver side window when the master control is depressed longer than 0.4 seconds.
^ The driver side window can be completely lowered when the master control is depressed between 0.04 and 0.4 seconds and then released.
Glass, Frames and Mechanisms - Module
Features and Operation:
The Generic Electronic Module (GEM) controls the opening of the LH driver side power window (window down motion) by activating the One Touch Down (OTD) window relay.
^ The driver side window has two downward motions, manual mode and auto mode. The down window mode is selected by pressing the LH window regulator control switch (master control). When the GEM detects that the master control switch has been depressed for a time greater than 0.4 seconds, it enters the manual mode. If the GEM detects that the master control switch was depressed between 0.04 and 0.4 seconds, it enters the auto mode.
The power window system will operate only if:
^ The ignition switch is in the RUN or ACC position (or)
^ The delayed accessory feature is in the active mode.
Modes of Operation
There are two modes of operation for the power window system:
Manual Mode:
When the LH window regulator control switch is pressed to the down position, the window will move down when the LH window regulator control switch is depressed longer than 0.4 seconds.
Feature Input:
^ LH window regulator control switch, first down position.
NOTE: Delayed accessory feature must be active.
Feature Output:
^ OTD relay coil output (grounded when activated, open circuit when deactivated).
Auto Mode:
Auto mode provides the OTD feature. The OTD feature is activated when the LH window regulator control switch, for the LH window, is pressed between 0.04 and 0.4 seconds, and then released.
Auto mode will be terminated when any of the follow conditions are met:
^ The LH window regulator control switch is pushed to the up position or down position.
^ Seven seconds have elapsed since auto mode was initiated.
^ A window regulator electric drive stall condition is detected on the OTD sense line inputs.
Feature Inputs:
^ LH window regulator control switch inputs; refer to the LH Front Window Regulator Control Switch Inputs Table.
^ OTD sense lines, high and low (voltage difference corresponds to window current).
^ Door open warning lamp switches (grounded when door is ajar, open circuit when door is closed).
NOTE: Delayed accessory feature must be active.
Feature Output:
^ Down window relay coil output (grounded when activated, open circuit when deactivated).
One Touch Down Relay
The GEM controls manual down and OTD window movement with the OTD relay.
The relay is activated by applying ground directly to one side of the down window relay coil, and is deactivated by removing the ground signal.
LH Front Window Regulator Control Switch Inputs Table
Delayed Accessory
Features and Operation:
The delayed accessory feature of the GEM provides power for the power window system. The following components are under the control of the delayed accessory relay:
^ LH window regulator electric drives.
^ RH window regulator electric drives.
The delayed accessory feature is active when:
^ The ignition is in the RUN position or ACC position, (or)
^ The ignition switch makes a transition from RUN or ACC to OFF, and all doors are closed.
NOTE: Delayed accessory is suspended (off) while the ignition is in the START position. The delayed accessory feature is re-activated when the ignition makes the transition from START to RUN. The delayed accessory feature becomes deactivated if:
^ Any passenger door becomes ajar when the ignition switch is in the OFF or KEY OUT positions.
^ Ten minutes have elapsed since the ignition made a transition from RUN or ACC to OFF.
Feature Inputs:
^ Ignition switch RUN position: 12 V on both RUN and RUN/ACC inputs.
^ Ignition switch ACC position: 12 V on RUN/ACC input only.
^ Door open warning lamp switches (grounded when door is ajar, open when door is closed
Feature Outputs:
^ Delayed accessory relay coil output (grounded when active, open circuit when inactive).
Heated Backlite and Mirror Timer
When the rear window defrost switch is pressed, a 10-minute timer is started and the GEM energizes a relay that provides battery voltage to the heated backlite and outside rearview mirror (if equipped). The rear window defrost heats up to defog the rear window or melt accumulated snow or ice.
GEM Controlled Functions
The GEM is equipped on four-wheel drive vehicles with power windows. The Central Timer Modules (CTMs) are equipped only on two-wheel drive vehicles without power windows.
NOTE: GEM diagnostics are compatible with scan tool, while CTM diagnostics are not.
The GEM incorporates the functions of several different modules into one, and offers diagnostics to easily locate and repair concerns affecting the subsystems that it controls.
The GEM constantly monitors the systems under its control and reports a concern in the form of a Diagnostic Trouble Code (DTC). A DTC can be retrieved with scan tool through the communications link.
The scan tool is a menu-driven tester that allows the user to run specific diagnostic tests. Scan tool can isolate faults in the GEM subsystems through a symptom-driven diagnostic procedure. Connecting the tester to the GEM communications link will not alert the GEM. If the GEM is "asleep" when then diagnostic connector is plugged in, the GEM must be "awakened." If the communication link cannot be established, it is advised to turn the ignition to RUN.
The GEM has a sleep function to minimize battery consumption. During the sleep mode, the GEM turns off all outputs and monitors the following:
^ Door ajar (Both front and rear doors, and liftgate).
^ Key in ignition.
^ Key in RUN or ACC.
^ Door handles (driver or passenger).
^ Two-step unlock switch (disarm switch).
^ Neutral safety switch.
^ Illuminated entry request - RAP module.
If a change of status occurs at one of these inputs while the GEM is asleep, the GEM will "wake up." When the GEM awakens, it performs an internal self test, and begins normal operation of its functions.
The GEM will go into the sleep mode immediately after both of the following conditions have been met:
^ Key in OFF or key not in ignition.
^ After 45 minutes have elapsed with no change to any wake-up input.
The GEM control system has two modes of operation, the normal operating mode and tester-dependent diagnostics mode.
The normal operation of the GEM can detect errors. An integral part of the normal GEM operation is the continued diagnostic capability. Continuous diagnostics detects errors, and changes the GEM control strategy. There is no warning lamp for the GEM: therefore, a DTC concern will direct you to the GEM. Examples of faults that may be detected during normal operation include:
^ GEM continuous self test (RAM, ROM, EEPROM, AID checking).
^ Output driver monitoring (open circuit/short to GND, short to battery).
^ Illogical combinations of input signals. The GEM can only detect open circuit/short to GND faults when the GEM is not energizing a load, and short to battery faults when the GEM is attempting to energize a load.
Delayed Accessory
The GEM controls the delayed accessory feature and the power supply to the power windows through the delayed accessory relay.
The relay is activated by applying ground directly to one side of the delayed accessory relay coil, and is deactivated by removing the ground signal.
Battery Saver
The following components are under the control of the battery saver relay:
^ Delayed accessory relay.
^ Overhead interior lamp with map lamps.
^ Overhead interior lamp switch.
^ Interior lamp relay coil.
The battery saver relay becomes active (relay coil is energized) when the GEM is in the awake mode, and is deactivated (relay coil is dc-energized) when the GEM is in the sleep mode.
The battery saver will remain active until the ignition state is not ACC or RUN and 45 minutes have passed since the last active input. At that time, the relay will be deactivated and power to the above circuits will terminate.
Five minutes after the battery saver relay has become deactivated, the GEM will go into a lower power state known as sleep mode. In the sleep mode, the GEM will deactivate all outputs and will monitor only select inputs.
Logical characteristics of the GEM battery saver mode are as follows:
Feature Input:
^ Sleep/awake mode status.
Feature Output:
^ Battery saver relay control (open circuit in sleep mode, grounded when awake).