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For 1990-2009 cars only

Sunroof Description and Operation Spoiler System

The sunroof spoiler system consists of a moving glass panel and a 2nd fixed glass panel located just behind the moving glass panel. The moving glass component slides over the top of the fixed glass, and the roof panel. There is also a power roller sunshade which covers both glass panels. The electrical portion of the system controls the opening and closing of the sunroof glass and the power roller sunshade.

The electrical portion of the spoiler sunroof system consists of:

    • Body control module (BCM)
    • Sunroof glass control module
    • Sunshade control module
    • Sunroof control switch assembly
    • Sunshade control switch assembly
    • Local interconnected network (LIN-Bus)

The sunroof electrical system uses a master/slave configuration utilizing a LIN-Bus based system for communication. The BCM is designated as the master, while the sunroof and sunshade control modules are configured as the slaves.

As the system master, the BCM uses the LIN-Bus communication bus to enable or disable sunroof and sunshade operation, communicate vehicle information to each controller, and request sunroof or sunshade movement. The sunroof/sunshade controllers provide system status and diagnostic information to the BCM for diagnostic reporting and operational purposes.

The sunroof glass and power sunshade are each controlled by its own integrated motor/controller containing the necessary electronics, motor, hall effect position sensors, as well as the interface to the driver control switches. Each motor/controller is capable of controlling motion based on control switch activation and LIN-Bus message commands from the system master.

There are times when the sunshade and sunroof operation are dependent on each other (see below). This dependency is controlled by the BCM because even though the sunroof controller and the sunshade controller reside on the same LIN-Bus they do not communicate directly with each other.

The integrated motor/controller used for glass control and for power sunshade control are actually the same physical part. All the operational software required to perform the glass and sunshade functions are contained in the one part. The function performed is determined by the grounding scheme of two function select input/output pins while the operational calibrations are loaded over the LIN-Bus communication bus by the sunroof system master, the BCM.

Sunroof Glass and Sunshade Control Switches

The sunroof and sunshade control switches are connected directly to their respective controllers and provide positions for open, express open, off, close, and express close. The control switch completes the circuit between two signals provided by the control module, a reference ground Input and a pull-up voltage provided by the analog to digital switch input. The control switch places a different resistor ladder network in the circuit depending on the function selected. The controllers analog to digital switch input reads the resulting voltage range and determines the function as indicated in the included charts.

System Protection Functions

Normal operation of the sunroof system may be altered by one of the following events.

Obstacle or Blockage Detection

When enabled, obstacle detection is active only while the sunroof or sunshade opening is approximately 4-200 mm (0.16-7.87 in) when moving in the closing direction. When an obstacle is detected in this range, the motion in the closing direction will stop and the sunroof/sunshade will reverse direction for a short distance. The reversal shall complete regardless of operating Mode. If the travel is outside the range defined above, the sunroof/sunshade will try to continue closing until it detects a motor stall condition or the system is at one of its defined stops.

Motor stall

If the sunroof or sunshade is moving in the open or close direction and stops moving for 350 ms while the switch or LIN-Bus command is active, and no obstacle has been detected, the motor shall be turned off to prevent overheating.

Sunroof System Thermal Protection

The sunroof/sunshade controllers have a thermal protection algorithm to protect the sunroof/sunshade controls and motors from damage due to overheating conditions resulting from immoderately switch actuations. The thermal protection algorithm will cause any new sunroof/sunshade open commands to be ignored until the motors are allowed to cool. A number of close requests during an over temperature condition will be allowed. If the thermal protection is triggered during an obstacle detection event, the sunroof/sunshade reversal shall be finished.

Coordination between Sunshade and Sunroof

There is an interaction between the sunshade and sunroof operation. The system master (BCM) will command the sunshade to open to predefined positions based on the requested sunroof position. This interaction may also prohibit the sunshade from closing past these points depending on the sunroof position.

Opening

If the Sunroof is opened anywhere between the fully closed and vent position, the BCM will command the sunshade to a minimum open position provided that the sunshade is opened less than this amount at the time of the sunroof command.

If the sunroof receives an ‘Open’ or ‘Express Open’ command taking the sunroof past the vent position, the BCM will command the sunshade to open approximately half-way if the sunshade is opened less than this amount at the time of the sunroof command. This position corresponds to a point behind the leading edge of a fully opened sunroof glass.

Closing

Only if the sunroof is fully closed will the sunshade be allowed to fully close with a normal close or express close command. If the sunroof is opened past the vent position, the sunshade will not be allowed to close past the ½ way point mentioned above with either a normal close or express close command. If the sunroof is not fully closed but is open less than or at the vent position, the sunshade will not close past the minimum open position mentioned above with either a normal close or express close.

Sunroof disabled with Sunshade faults

When there is interaction between the sunroof and sunshade the sunroof shall be disabled if the sunroof is fully closed and any of the following sunshade faults are reported:

   • 

Motor fault

   • 

Sensor fault

   • 

Thermal protection is active

   • 

Sunshade not normalized

   • 

Sunshade not configured

   • 

Application failed

Service Tool Commanded Open

When a service tool commands the sunshade open, it results in the Sunshade going to ½ way point mentioned above or to the fully open depending on the calibration. If the ½ way point is calibrated on, this position is as far as the sunshade can be opened with the service tool. To go beyond this point a switch activation must be used.

Sunroof Operation

Open to Vent Position

When the position of the sunroof is less than the defined vent position, activating the sunroof 'Open' switch for less than 500 ms results in the sunroof moving until it reaches the vent position.

Normal Open (Non-Express)

When the sunroof switch is held in the 'Open' position, the sunroof begins opening. As long as the switch is continuously held in the ‘Open’ state the sunroof will not stop in the vent position.

Sunroof Express Open

When the sunroof control switch transitions to the 'Express Open' state, the Sunroof will ' express open ' until the controller determines the Sunroof has reached the ' Comfort Stop' position or the ' Fully Open ' position, or the switch transitions to another state after first returning to the ‘Off’ position.

Normal Close (Non-Express)

When the sunroof switch is in the "Close" state, the sunroof will begin moving in the closed direction.

Sunroof Express Close

When the sunroof control switch transitions to the 'Express Close' state, the Sunroof will express ' close 'until the controller determines the sunroof has reached the fully closed position, or the switch transitions to another state after first returning to the ‘Off ’ position. The sunroof motion will cease if the switch transitions back to the ‘Close’ or ‘Express Close’ state after returning to the ‘Off ’ position first.

Sunshade Operation

Sunshade Normal Open (Non-Express)

When the sunshade switch is held in the 'Open' position, the sunshade begins opening.

Sunshade Express Open

When the sunshade control switch transitions to the 'Express Open' state, the sunshade will ' express open ' until the controller determines the sunshade has reached the ' fully open ' position, or the switch transitions to another state after first returning to the ‘Off ’ position.

Sunshade Normal Close (Non-Express)

When the sunshade switch is in the 'Close' state, the sunshade will begin moving in the closed direction until the switch returns to the ‘Off ’ position, or there is a sunroof coordination operation active and it reaches one of the positions described above, or the controller determines the sunshade has reached its fully closed position.

Sunshade Express Close

When the sunshade control switch transitions to the 'Express Close' state, the sunshade will express ' close ' until the controller determines the sunshade has reached the fully closed position, there is a sunroof coordination operation active and it reaches one of the positions described below, or the switch transitions to another state after first returning to the ‘Off ’ position. The sunshade motion will cease if the switch transitions back to the ‘Close’ or ‘Express Close’ state after returning to the ‘Off ’ position first.

Sunroof Description and Operation Tilt and Slide System

The tilt/slide sunroof consists of a moving glass panel and a manual sunshade. In the tilt/slide sunroof system the rear of the glass tilts up for venting and slides between the head liner and roof panel as it slides open. The glass is controlled by an integrated motor/controller. The sunshade has a mechanical connection to the glass causing it to open with the glass and keeping it from closing more than the glass.

The electrical portion of the tilt/slide sunroof system consists of:

    • Body control module (BCM)
    • Sunroof glass control module
    • Sunroof control switch assembly
    • Vent control switch assembly
    • Local interconnected network (LIN-Bus)

The sunroof electrical system uses a master/slave configuration utilizing a LIN-Bus based system for communication. The BCM is designated as the master, while the sunroof control module is configured as the slave.

As the system master, the BCM uses the LIN-Bus communication bus to enable or disable sunroof operation, communicate vehicle information to the sunroof controller, and request sunroof movement. The sunroof controller provides system status and diagnostic information to the BCM for diagnostic reporting and operational purposes.

The sunroof glass is controlled by a integrated motor/controller containing the necessary electronics, motor, hall effect position sensors, as well as the interface to the driver control switches. The motor/controller is capable of controlling motion based on control switch activation and LIN-Bus message commands from the system master.

The operational calibrations for the sunroof integrated motor/controller are loaded over the LIN-Bus communication bus by the sunroof system master, the BCM.

Sunroof Glass and Sunshade Control Switches

The sunroof control switches are connected directly to the controller. The sliding glass switches provide detent positions for open, express open, off, close, and express close. The vent switches provide detent positions for open, off, and close. The control switch completes the circuit between two signals provided by the control module, a reference ground input and a pull-up voltage provided by an analog to digital switch input. The control switches place a different resistor ladder network in the circuit depending on the function selected. The controller’s analog to digital switch input reads the resulting voltage range and determines the function as indicated in the included charts.

System Protection Functions

Normal operation of the sunroof system may be altered by one of the following events.

Obstacle or Blockage Detection

When enabled, obstacle detection is active only while the sunroof opening is approximately 4-200 mm (0.16-7.87 in) when moving in the closing direction. When an obstacle is detected in this range, the motion in the closing direction will stop and the sunroof will reverse direction for a short distance. The reversal shall complete regardless of operating Mode. If the travel is outside the range defined above, the sunroof will try to continue closing until it detects a motor stall condition or the system is at one of it’s defined stops.

Motor stall

If the sunroof is moving in the open or close direction and stops moving for 350 ms while the switch or LIN-Bus command is active, and no obstacle has been detected, the motor shall be turned off to prevent overheating.

Sunroof System Thermal Protection

The sunroof controllers have a thermal protection algorithm to protect the sunroof controller and motor from damage due to overheating conditions resulting from immoderately switch actuations. The thermal protection algorithm will cause any new sunroof open commands to be ignored until the motor is allowed to cool. A number of close requests during an over temperature condition will be allowed. If the thermal protection is triggered during an obstacle detection event, the sunroof reversal shall be finished.

Sunroof Operation

Vent

Open to Vent Position

When the sunroof is closed or in a partial vent position and the sunroof vent open switch becomes active, the sunroof shall begin to 'Express open' to the vent position. sunroof motion shall cease when the Sunroof reaches the vent position or if the sunroof sliding glass switch becomes active.

Close from Vent

When the sunroof is in the vent position and the sunroof vent switch enters the 'Close' state, the sunroof will begin to express close the sunroof. Motion will continue until the sunroof has reached its fully closed position or if the sunroof sliding glass switch becomes active.

Sliding Class

Normal Open (Non-Express)

When the sunroof is not in a vent position and the sunroof sliding glass switch is held in the 'Open' position, the sunroof will begin opening. Motion will continue until the switch returns to the 'Off' state or the vent switch transitions to any active state.

Sunroof Express Open

When the sunroof control switch transitions to the 'Express Open' state and the sunroof is not in a vent position, the sunroof will express open until the controller determines the sunroof has reached the comfort stop position or the fully 'Open' position, the switch transitions to another state after first returning to the ‘Off’ position, or the vent switch transitions to an active state.

Normal Close (Non-Express)

When the sunroof switch is in the 'Close' state and the sunroof is not in the vent position, the controller will begin moving the sunroof in the close direction. If the vent switch becomes active the motor will be turned off.

Sunroof Express Close

When the sunroof switch is in the 'Express Close' state and the sunroof is not in a vent position, the sunroof will express close until the controller determines the sunroof has reached the fully closed position, or the switch transitions to another state after first returning to the ‘Off ’ position. The sunroof motion will cease if the switch transitions back to the ‘Close’ or ‘Express Close’ state after returning to the ‘Off ’ position first or the vent switch transitions to any active state.