Power Sunroof System Components
The power sunroof system consists of the following components: 
|     •  | Sunroof opening position switch/sunroof position encoding system
switch | 
 
|     •  | Sunroof glass, tilt/slide type with glass sliding between roof
 and headliner | 
 
|     •  | Rail and track assembly upon which the sunroof glass rides | 
 
|     •  | Power supply for the sunroof module: PWR WINDOWS, 30 A
 circuit breaker | 
 
Power Sunroof Operation
The power sunroof will operate with the ignition switch turned to Accessory
 or RUN. Once the ignition switch is turned to OFF the sunroof will continue
  to operate until any door is open or when the Retained Accessory Power (RAP)
  has timed out. For a description and operation of the RAP operation, refer
  to 
Retained Accessory Power (RAP) Description and Operation 
 in Retained Accessory Power.
Use the rocker type sunroof switch, located in the front center of the
 headliner, to command the sunroof to :
Pressing the sunroof switch, rearward portion, the sunroof glass will
 slide from:
|     •  | Vent position to the closed position. | 
 
|     •  | Closed position to the open position. | 
 
Pressing the sunroof switch, forward portion, the sunroof glass will
 slide from:
|     •  | Open position to the closed position. | 
 
|     •  | Closed position to the vent position. | 
 
To Vent Open
To open the power sunroof to the vent position from the closed position,
 turn the ignition to ON, with engine OFF. Press and hold the forward portion
 of the sunroof switch. This will apply the sunroof switch low reference to
 the  sunroof switch close signal circuit, 5 volt reference, input
to  drop  to 0 volts. As long as the sunroof module sees a constant
input of 0 volts at the sunroof switch close signal circuit input,
the rear portion of the sunroof glass will raise upward to the full vent 
position.  The sunroof glass will soft stop at the full vent position based
 on  the inputs from the sunroof limit switches. To stop the sunroof glass
in a position   other than the full vent position, release the sunroof switch
when the sunroof glass reaches the desired vent position. The sunshade will
have to manual   slid open.
To Close from Vent Position
To close the power sunroof from the vent position, turn the ignition
 ON, with the engine OFF. Press and hold the rearward portion of the sunroof
 switch.  This will apply the sunroof switch low reference to the sunroof
switch  open  signal circuit, 5 volt reference, input to drop to 0 volts.
  As long as the sunroof module sees a constant input request of 0 volts
at the sunroof switch open signal circuit input, the sunroof glass will continue
to  lower downward to the closed position. The sunroof  glass  will soft stop
at the closed position based on the inputs from the sunroof limit switches.
The sunshade will have to be manually slid closed.
Express Open
The express open will work only with the glass in between the closed
 and partially open positions. To express open the power sunroof, turn the
  ignition ON, with engine OFF. Press the rearward portion of the sunroof
switch  once. This will apply the sunroof switch low reference  to the sunroof
switch signal open signal circuit, 5 volt reference, input to drop
to 0 volts  momentarily. The momentary 0 volts  input to the
sunroof module indicates  an express open request. The  sunroof glass will
lower slightly, then begin  to automatically express  open between the roof
and headliner. The sunroof  glass will soft stop at the full open position
 based on the inputs from the  sunroof limit switches. As the sunroof glass
expresses  open so will the sunshade.  To stop the sunroof glass in a desired
position  other than to the express  open position, as the sunroof is expressing
open, press the sunroof switch  again, in either direction, to stop the movement. 
To Close from Open Position
To close the power sunroof from the open position is the same as to
 opening to the vent position. Turn the ignition ON, with   the engine OFF.
Press and hold the forward portion of the sunroof switch.  This  will apply
the sunroof switch low reference to the sunroof switch close  signal  circuit,
5 volt reference, input to drop to 0 volts. As  long  as the
sunroof module sees a constant input request of 0 volts at the sunroof
switch close signal circuit input, the sunroof glass will continue to the
closed position. The sunroof glass will soft stop at the closed position based
on the inputs from the sunroof limit switches. The sunshade   will have to
be manually slide closed.
Sunroof Motor
The sunroof has a bi-directional motor. When the motor is not operating
 both sunroof motor control circuits are grounded. When the motor drives the
sunroof glass in the   direction from the vent to closed or closed to open
position, the following   occurs:
|     •  | Voltage is supplied to the sunroof motor open control circuit. | 
 
|     •  | Ground is maintained to the sunroof motor close control circuit. | 
 
When the motor drives the sunroof in the direction from the open to
 closed or closed to vent position, the following occurs:
|     •  | Voltage is supplied to the sunroof motor close control circuit. | 
 
|     •  | Ground is maintained to the sunroof motor open control circuit. | 
 
The sunroof module is equipped with a timer circuit which stops the
 operation of the sunroof motor after 8 seconds.
Sunroof Opening Position Switch/Sunroof Position Encoding System Switch
The sunroof opening position switch/sunroof position encoding system
switch tracks various positions of the sunroof glass through its travel between
full vent  to full open.
The sunroof module monitors the sunroof limit switches LS1, LS2 and
LS3 inputs. As a sunroof limit switch  closes, the sunroof limit switch circuit,
5 volt reference, will  be  shorted to the sunroof limit switch low
reference circuit, pulling the  reference  voltage to 0 volts. The
sunroof module understands  the position of  the sunroof glass based on the
multiple input combinations  to the limit  switch inputs. The various inputs
allow the sunroof module to bring the sunroof glass to a soft  stop when it
reaches the full vent, full open or closed positions.