I have a 1999 chevy blazer I cannot close the

The sunroof is powered by the same circuit breaker that power's your power window, so if your windows work than the circuit breaker should be good. You needed test the switch to verify if works with; on the factory sunroof system the roof is controled by a sunroof module the module receives a signal from the switch then throws voltage to the sunroof motor. The motor and module are located between the sunroof assembly and windshield underneath the head liner. You would reconnected the switch and test to see if the sunroof motor is getting power when the switch is in use by testing the dark green wire when closing and a light green wire when opening. Test these wires at the sunroof motor with a ohm meter or test light. Also, check this procedure to repair...

GM S-Series Pick-ups and SUV's 1994-1999 Repair Guide Power Sunroof - REMOVAL & INSTALLATION

Glass

1. Close the sunroof and open the sunshade.
2. If the piece of glass being removed is to be reinstalled, mark the location of the screws, this will ensure proper alignment during installation.
3. Unfassten the screw that attach the sunroof glass to the sunroof assembly.
4. Remove the glass from the vehicle.
   

1. Place the glass into position and install the screws that retain the glass. Do not fully tighten the screws just yet.
2. Adjust the glass so that the fit between the glass and the opening is equal at all four sides. The rear edge of the glass may be slightly higher than the front edge to reduce the wind noise.
3. After the glass has been adjusted, tighten the screws to 31 inch lbs. (3.5 Nm).
4. Check the operation and fit of the glass.
   

1. Disconnect the negative battery cable.
2. Remove the sunroof opening trim by starting at the **** joint and pulling the trim strip from the sunroof opening.
3. Remove the headlines as follows:
   1. If equipped, remove the overhead or sunroof console.
   2. If equipped, remove the dome lamp.
   3. Remove the coat hooks and the assist handles.
   4. Remove the sunshade-to-roof screws, while pulling down on the sunshade base, push in on the extended screws, loosen the screw that attaches sunshade to the roof and pull down on the sunshade retainer while pushing in on the extended screw. Remove the retainer.
   5. Remove the windshield garnish moldings using trim removal tool J 38778 or its equivalent. Pull the molding away from the pillar and up to remove it.
   6. On four door models, remove the body lock pillar trim panels.
   7. Remove the roof rear header garnish molding using the trim removal tool. Insert the tool into the front edge of the trim and work along the front of the panel, from one end to the other. Unplug the cargo lamp electrical connection and remove the trim.
   8. On two door models, remove the rear seat upper seat belt anchor bolts.
   9. Remove the upper and lower front seat belt anchor bolts.
   10. Remove the rear seat belt lower anchor nut (two door models only).
   11. Remove the end gate or liftgate opening sill plate.
   12. Remove the jack storage cover (left side).
   13. Remove the upper body side trim panel screw (left side).
   14. Remove the upper body side trim panel and the body side front lower trim panel.
   15. Remove the headliner from the vehicle.
4. Remove the sunroof console mounting bracket.
5. Remove the straps that retain the wiring harness.
6. Tag and unplug any necessary electrical connections.
7. Unfasten the screws that attach the motor to the sunroof assembly.
8. Remove the motor from the vehicle. Make sure that you do not move the sunroof mechanism while the motor is not in place.
   

1. Place the motor into position and install the retaining screws. Tighten the screws to 31 inch lbs. (3.5 Nm).
2. Attach all electrical connections that were unplugged.
3. Attach the straps that retain the wiring harness.
4. Install the sunroof console mounting bracket.
   

1. Install the headliner as follows:
   1. Install the body side front lower trim panel and the upper body side trim panel.
   2. Install the upper body side trim panel screw (left side).
   3. Install the jack storage cover (left side).
   4. Install the end gate or liftgate opening sill plate.
   5. Install the rear seat belt lower anchor nut (two door models only). Tighten to 59 ft. lbs. (80 Nm).
   6. Install the upper and lower front seat belt anchor bolts. Tighten the bolts to 52 ft. lbs. (70 Nm).
   7. On two door models, install the rear seat upper seat belt anchor bolts. Tighten the bolts to 52 ft. lbs. (70 Nm).
   8. Install the roof rear header garnish molding. Attach the cargo lamp electrical connection, place the trim in position and engage the molding retainers.
   9. On four door models, install the body lock pillar trim panels.
   10. Install the windshield garnish moldings. Place the molding into position, align the retainer clips with the slots and press into place.
   11. Place the sunshade retainer in position, install the screw and tighten to 10 inch lbs. (1.1 Nm). Position the sunshade, install the screws and tighten to 10 inch lbs. (1.1 Nm).
   12. Install the coat hooks and the assist handles.
   13. If equipped, install the dome lamp.
   14. If equipped, install the overhead or sunroof console.
       
2. Install the sunroof opening trim. Start the trim in the center of the front of the sunroof opening and work around the perimeter.