My 1999 Jeep Grand Cherokee Limited sun roof does not want to open.

If your motor is audible and your fuses and connectors are okay, you may have to take a close look at the plastic gear parts up in the roof. The nylon parts do wear out since they are in the roof and more exposed to different temperatures. If any of that mechanism fails then your sunroof will stop working even if the motor is still good. It is a bit of a PITA to get to it since you will have to remove the headliner to get at the mechanism and then identify the worn part and replace it CAUTION: The sunroof system is timed from the factory so that the motor shuts off automatically when the sunroof window reaches a certain position. Extreme care must be taken when removing the motor, timing may be thrown off causing possible damage to the sunroof system. Anytime the motor is removed from the sunroof assembly the sunroof glass panel must be in the FULLY CLOSED POSITION or the unit will be out of timing. The drive motor cannot be reset to the park position after being removed.
CAUTION: The sunroof motor should only be powered through the vehicle battery and sunroof wire harness. Applying power to the sunroof motor leads will cause failure of the control module.
Move glass panel to the fully closed position.
Move glass panel to the fully closed position.
Remove the A-pillar trim. (Refer to 23 - BODY/INTERIOR/A-PILLAR TRIM - REMOVAL)
Remove the B-pillar upper trim. (Refer to 23 - BODY/INTERIOR/B-PILLAR UPPER TRIM - REMOVAL)
Remove the C-pillar trim. (Refer to 23 - BODY/INTERIOR/C-PILLAR TRIM - REMOVAL)
Remove the D-pillar trim. (Refer to 23 - BODY/INTERIOR/D-PILLAR TRIM - REMOVAL)
Remove the sunvisors. (Refer to 23 - BODY/INTERIOR/SUN VISOR - REMOVAL)
Remove the overhead console. (Refer to 8 - ELECTRICAL/OVERHEAD CONSOLE - REMOVAL)
Disconnect the control switch wire connector.
Remove headliner as necessary to gain access to sunroof drive motor. Refer to Headliner Removal and Installation for proper procedures.
Disconnect the drive motor wire harness connectors (Sunroof Drive Motor and Express Module).
Remove drive motor fasteners and remove motor from the sunroof housing