Windows: Description and Operation
GLASS, FRAMES AND MECHANISMSThe windshield consists of:
- standard tempered safety glass
- a window opening flange bonded with urethane adhesive
The fixed rear window consists of:
- a standard tempered safety glass
- a window opening flange bonded with foam butyl sealant and studs with nuts
The power rear window consists of:
- a standard tempered safety glass
- a window control switch
- a window regulator
- a window motor
The front door window consists of:
- a standard tempered safety glass
- a window control switch
- a window regulator
- a window regulator motor
The rear door window consists of:
- a standard tempered safety glass
- a window control switch
- a window regulator
- a window regulator motor
Glass, Frames and Mechanisms - Window Control
The window control switch:
- is located on each door trim panel.
- may be used to raise or lower both passenger side and driver side windows from the master control on the driver door.
- includes a window lock feature that is controlled through the master control.
- if located in the master control on the driver door trim panel, can manually lower the driver side window when pressed to the first detent position.
- if located in the master control on the driver door trim panel, can automatically lower the driver side window in one-touch down (OTD) mode when pressed to the second detent.
The power rear window control switch:
- is located in the instrument panel center finish panel.
- will move the power rear window glass to one of three preset positions: fully open, fully closed and vent.
PRINCIPLES OF OPERATION
Features and Operation
The power window system operates under the control of the accessory delay relay. The instrument cluster module (ICM) will ground the relay coil to provide power to the power window system.
The power window system can be operated from the driver window control switch or from the window control switch located on each door panel. The driver window control switch has two modes of operation for the driver power window, manual and auto. All other windows operate in the manual mode only.
Auto Mode
Auto mode provides the one-touch down (OTD) feature for the driver front power window. The OTD function allows the driver front power window to be completely lowered when the driver window control switch is pressed to the second detent position and then released. OTD is controlled internally by the driver window control switch.
Power Rear Window
NOTE: The power rear window motor is not on the multiplex link.
The instrument cluster module (ICM) controls accessory delay power to the rear power window motor by providing ground to the accessory delay relay coil when the ignition switch is turned to either the RUN or ACC positions.
The power rear window motor is a 8-pin motor with integral electronics. The power rear window control switch is located on the instrument panel adjacent to the radio and provides a ground signal to the motor to signal an open, close or vent request. The integral electronics on the motor allow the power rear window to be moved to three positions: fully open, fully closed and vent (approximately two inches down from fully closed). The control switch is rotated clockwise and released to fully close the window, rotated counterclockwise and released to fully open the window, and pushed and released to actuate the window to the vent position.
The power rear window motor plastic pinion gear is mated to the drum housing of a single rail drum and cable window regulator. The motor is attached to the plastic drum housing by three screws. The motor uses internal Hall effect sensor feedback coupled to the microprocessor, to determine window position and operate the power rear window. If the microprocessor is not receiving the Hall effect sensor pulses, the motor will run for approximately half a second, then enter error mode (window will become inoperative). The motor contains a thermal breaker to protect the motor windings from over-current/over-temperature operation. Continued successive operation of the motor will cause the thermal breaker to open, causing a loss of function until the power rear window motor cools.
The power rear window motor operates only with the ignition switch in the RUN/ACC position, or when the accessory delay relay is active and is sensed by the accessory delay relay and logic ground inputs. The motor is supplied with battery power and draws a key off load of approximately 1 mA. All of the high current required to move the window is supplied through the battery and motor ground inputs. The loss of either logic or motor ground will cause this system to become inoperative. For correct functionality, both power feeds and both ground feeds must be intact at the power rear window motor.
If a down or vent command is selected while the ignition switch is in the RUN/ACC position, and the ignition switch is turned to OFF or START without accessory delay relay power enabled, the window will move to the fully open or vent position and stop. If an up command is selected while the ignition switch is in the RUN/ACC position, and the ignition switch is turned to OFF or START without accessory delay relay power enabled, the window will stop if it is between vent and fully closed, or will move to the vent position and stop if it is between vent and fully open.
If an obstacle is detected in the power rear window opening as the window is closing UP, the window will automatically reverse direction and move toward the fully open position. This is known as "bounce-back". Once the window stops at its bounce-back position, and within two seconds the switch is released, then held in the UP position, the window will travel up with no bounce-back protection (security override). If the ignition switch is turned to OFF or START without accessory delay power enabled, the window will reverse direction with bounce-back re-enabled. Ice, contaminant buildup, and environmentally induced tight spots in the window seals are all possible uses for the security override feature.
If power (B+) is disconnected from the power rear window motor while the window is in motion, the motor will enter position recovery mode when power is restored. Position recovery mode allows up and down movement of window in 15 mm (0.6 in) increments until the motor stalls the window glass in the upper header seal. If no internal or external faults exist, the motor will automatically resume normal operation.
The power rear window control switch is supplied with illumination and illumination ground inputs used to illuminate the control switch when the headlamp switch is turned to the PARK or ON position. The autolamp position may also energize this input. These switch inputs do not affect operation of the window. The control switch uses the main ground input which is transferred to the open, closed, or vent outputs by closing a switch contact. If the main ground signal is missing, the window will become inoperative.
If the power rear window control switch, or its associated wiring, develops an open circuit, that function will become inoperative. If the open contact or associated wiring develops an open circuit, the window will only travel to the vent or fully closed positions. If the close contact or associated wiring develops an open circuit, the window will only travel to the fully open or vent positions. If the vent contact or associated wiring develops an open circuit, the window will only travel to the fully open or closed positions.
The power rear window motor will suspend normal operation if a power rear window control switch error exists. A control switch error is defined as open and close, open and vent, close and vent, or open, close and vent energized at the same time. The window will be inoperative if a control switch error is present.
If the motor is removed from the window regulator drum housing, or if a new motor is installed, the window must be initialized. A new motor will be in error mode and inoperative until initialized. For positioning the window regulator for glass removal/installation, refer to Rear Window Positioning.
The power rear window will automatically adjust to system changes throughout its life. Changes in seal drag and slight changes in the fully closed position will occur and are automatically compensated for. Once initialized, the motor will soft stall into the upper and lower positions, contributing to the extended durability of the system.