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For 1990-2009 cars only

Sunroof Description and Operation w/RPO C3Y

Power Sunroof System Components

The power sunroof system consists of the following components:

    • One tilting glass sunroof panel--For sunroof vent functions
    • Three sliding glass sunroof panels, which allow the sunroof to open in sections
    • Power sunshade panel--An adaptable panel which is rolled out or rolled in and stored by the sunshade motor/actuator in order to cover or uncover the sunroof glass panels
    • Power sunroof switch--A rotary style switch controlling sunroof switch signal inputs to the sunroof motor/actuator
    • Power sunshade switch--A momentary press style switch controlling sunshade switch signal inputs to the sunshade motor/actuator
    • Power sunroof motor/actuator--Comprised of both the sunroof motor/actuator and the sunroof electronic control module, it is sometimes referred to as the sunroof control module/motor assembly.
    • Power sunshade motor/actuator--Comprised of both the sunshade motor/actuator and the sunshade electronic control module, it is sometimes referred to as the sunroof slave module.

Sunroof Motor/Actuator and Sunroof Switch

The sunroof motor/actuator assembly is located at the rear of the passenger compartment, above the rear view window, between the headliner and the roof structure. The sunroof motor/actuator assembly also contains the sunroof electronic control module and the two components are serviced together as a unit.

Battery positive voltage is supplied to the motor/actuator at all times through the 25-amp LAMELLA ROOF fuse located in the rear fuse block. Whenever the ignition is turned to RUN or ACCESSORY, or when the retained accessory power (RAP) system is active, the motor/actuator is also supplied battery positive voltage through the accessory voltage circuit and the 10-amp ROOF/HEAT SEAT fuse which is located in the body control module (BCM). The sunroof motor/actuator is grounded through splice S403 to body ground G302.

The sunroof motor/actuator supplies voltage to the sunroof switch through three internal resistors and three hard wire circuits. The 3 hard wire circuits are:

    • Sunroof switch data 1 signal circuit
    • Sunroof switch data 2 signal circuit
    • Sunroof switch data 3 signal circuit

The sunroof switch, which is also grounded to G302, is a rotary style switch. When the switch control lever is turned in a rotational direction, the appropriate switch contacts and signal circuits for the selected mode are simultaneously opened and/or closed to ground in order to provide the appropriate combination of voltage signals to the sunroof motor/actuator. The sunroof motor/actuator interprets the signals, and then applies battery positive voltage and ground to the appropriate circuits of the integral power sunroof motor in order to move the sunroof glass panels. At the same time, the sunroof motor/actuator sends a serial data message, via the keyword 2000 serial data circuit, to the sunshade motor/actuator to open the sunshade panel in conjunction with the sunroof glass. As the sunroof glass panels slide rearward to the open position, the sunshade motor/actuator simultaneously rolls in the adaptable sunshade panel.

The sunroof switch is mounted in a bezel which is located above the rearview mirror.

Sunshade Motor/Actuator and Sunshade Switch

The sunshade motor/actuator assembly is also located between the headliner and the roof structure, near the sunroof motor/actuator. The sunshade motor/actuator, also contains the sunshade electronic control module and the 2 components are serviced together as a unit. The sunshade motor/actuator receives battery positive voltage and ground from the same sources as the sunroof motor/actuator; from the LAMELLA ROOF 25-amp fuse and body ground G302 respectively.

The sunshade switch, a momentary press style switch, is located in the same bezel as the sunroof switch, above the rearview mirror. It receives battery positive voltage from the sunroof motor/actuator, via the sunshade switch open signal circuit and the sunshade switch close signal circuit. The sunshade switch is also grounded to body ground G302. When the switch is operated, the signal circuit for the selected mode is closed to ground, the voltage is pulled low, and the appropriate sunshade signal is provided to the sunroof motor/actuator. The sunroof motor/actuator interprets this signal, then sends a serial data message via the keyword 2000 serial data circuit to the sunshade motor/actuator to operate the sunshade panel. The sunshade motor/actuator then applies battery positive voltage and ground to the appropriate circuits of the integral power sunshade motor in order to roll in or roll out the sunshade panel.

Using the sunshade switch, the sunshade panel can be operated independently of the sunroof glass panels, however, it can never be closed to a position in which it is more closed than the sunroof glass.

Sunroof and Sunshade Operation

To operate the sunroof, the ignition must be in the RUN or ACCESSORY position, or the retained accessory power (RAP) system must be active. Using only the sunroof switch, both the sunroof and sunshade may be opened to the following positions:

    • Switch position 0:
       - The tilting glass vent panel and three sliding glass panels are completely closed.
       - The adaptable sunshade panel is rolled out to its closed position in which all four of the glass sunroof panels are covered.
    • Switch position 1 (Vent position):
       - The sunshade panel travels rearward to uncover the glass vent panel.
       - The rearward edge of the glass vent panel tilts upward to a position in which it is half open. One space of sunroof is now partly open.
    • Switch position 2:
       - The sunshade panel travels rearward to uncover the first sliding glass panel.
       - The vent panel tilts upward to its full open position.
       - The rearward edge of the third sliding glass panel tilts partially upward as all three sliding panels slide rearward to a position in which the third panel is stacked upon the rear section oft he sunroof opening. Including the sunroof vent space, tow spaces of sunroof are now open.
    • Switch position 3:
       - The sunshade panel travels rearward to uncover the second sliding glass panel.
       - The vent panel remains full open.
       - The rearward edge of the second sliding glass panel tilts partially upward as the remaining 2 sliding panels slide rearward to a position in which the second sliding panel is now stacked upon the third sliding panel. Including the sunroof vent space, three spaces of sunroof are now open.
    • Switch position 4:
       - The sunshade panel travels rearward to uncover the third sliding glass panel.
       - The vent panel remains full open.
       - The rearward edge of the first sliding glass panel tilts partially upward as it slides rearward to a position in which the first sliding panel is now stacked upon the second and third sliding panels. Including the sunroof vent space, four spaces of sunroof are now open.

From the fully open position, the sunroof switch may be used in the reverse order to close the glass panels to each of the individual positions described above. However, the sunshade will only close in conjunction with the sunroof glass to the first closed position. From there, the sunshade switch must be used to continue closing the sunshade.

Important: If the sunroof motor/actuator assembly has been replaced, or has lost battery positive voltage or ground for any other reason, it will be necessary to initialize the motor/actuator when service has been completed. Refer to Sunroof Control Module Programming and Setup.

Sunroof and Sunshade Express Operation

The sunroof glass and sunshade can also be express opened and closed. By rotating the sunroof switch directly from the full close position to the full open position, the vent glass, sliding glass panels, and sunshade are all fully opened in a synchronized, systematic series of movements. By rotating the sunroof switch directly from the full open position to the full close position, the glass sliding and vent panels can also be fully closed in a synchronized, systematic series of movements, while the sunshade rolls out only enough to cover the third sliding glass panel. From this position the sunshade switch must be used to finish fully closing the sunshade.

By using only the sunshade switch, the sunshade may be opened and closed independently of the sunroof glass, however, as previously stated, it can never be closed to a position in which it is more closed than the sunroof glass.

Sunroof Water Drainage

Any water that passes the roof seal is drained from the sunroof tray by 4 tubes that lead from the corners of the tray to the rocker panels of the vehicle. The tray which acts as a framework for the sunroof assembly, has a water channel that encircles the sunroof opening and directs the water to the drain tubes.

Sunroof Description and Operation w/RPO CF5

The sunroof system is controlled by the sunroof switch and the sunroof control module/motor assembly, which is also known as the motor/actuator assembly.

The sunroof control module is supplied battery positive voltage at all times through the 15-amp SUNROOF fuse located in the rear fuse block. Whenever the ignition is turned to RUN or ACCESSORY, or when the retained accessory power (RAP) system is active, the module is also supplied voltage through the accessory voltage circuit and the 10-amp SUNROOF/HTD SEAT fuse located in the body control module (BCM). The sunroof control module is grounded through the ground circuit and rear fuse block to a body ground stake.

The sunroof control module/motor is located between the headliner and the roof structure, while the sunroof switch is located above the rearview mirror. The sunroof control module supplies voltage to the contacts of the sunroof switch through the sunroof switch close signal circuit and the sunroof switch open signal circuit. The sunroof control module also supplies ground to the switch contacts through the sunroof switch low reference circuit. When the switch is operated, the contacts and signal circuit for the selected mode are closed to ground, the voltage is pulled low in the module, and the appropriate signal is recognized by the control module. The control module then internally applies battery positive voltage and ground to the appropriate circuits of the reversible power sunroof motor in order to move the sunroof glass panel to the open, close, or vent position.

Both the sunroof control module and the sunroof motor are integral parts of the sunroof control module/motor assembly and are not service separately.

To operate the sunroof, the ignition must be in the RUN or ACCESSORY position, or the RAP system must be active. When the sunroof panel is in the closed position, it can be raised to the vent position by pressing the OPEN/VENT side of the switch lever once. The panel may then be either expressed to the fully opened position by momentarily pressing the OPEN/VENT side of the switch lever a second time, or it may be adjusted to any preferred open position by pressing and holding the OPEN/VENT side of the switch lever until the panel has reached the desired position. To fully close the sunroof panel, press and hold the CLOSE side of the switch lever. Release the CLOSE side of the switch lever in order to stop the panel at any preferred closed position. Whenever the sunroof panel is in the express open mode, it can be stopped by momentarily pressing either side of the switch.

As the sunroof panel opens, it moves the sunshade to the open position as well. The sunshade can be manually opened and closed from inside of the vehicle while the glass panel is in the closed position. The sunshade is designed to stay in the open position while the glass panel is in the open position.

Important: 

   • If, during service, the sunroof control module has lost battery positive voltage or ground, or has been replaced, it will be necessary to initialize the control module once service has been completed. Refer to Sunroof Control Module Programming and Setup.
   • The sunroof can be manually cycled with a regular screwdriver, once the headliner is removed. This screwdriver fits into the drive gear, and when turned will operate the sunroof drive cables and simultaneously open or close the sunroof.

Any water that passes the roof seal is drained from the sunroof tray by 4 tubes that lead from the corners of the tray to the rocker panels of the vehicle. The tray which acts as a framework for the sunroof assembly, has a water channel that encircles the sunroof opening and directs the water to the drain tubes.