There are multiple reasons why the passenger-side window on the Ford Focus might need work. If the glass has been broken or cracked, it needs replacing for safety reasons. If the regulator containing the glass is not working properly, it can break the window and possibly damage other components in the door. You need to remove the door's inner trim panel in order to remove and replace the window glass and/or the regulator.
Disconnect the car's negative battery cable.
Remove the cover trim on the door's grab handle and the small plastic screw cover in the door handle cavity using a screwdriver. Remove the screws inside the pull handle and the cavity, then slide the bezel off the door handle.
Disconnect the electrical connector from the window's control switch.
Unscrew all of the securing screws along the outer edge of the trim panel, then pull the panel away from the door and rotate it upward at the back to remove it.
Take out the oddly shaped impact bolster by rotating it counterclockwise to release it from its retaining clips. Remove the retaining clips afterward.
Disconnect the speaker from the door by removing the four mounting screws with a screwdriver and disconnecting its wiring.
Unclip the door release handle from the door's front end and slide it out forward to remove it. Leave the cable connected to the handle.
Cut the butyl strip on the plastic weather shield with a knife, and peel the plastic from the door. Don't touch the adhesive on the plastic.
Reconnect the window controls to the electrical connector, and lower the window until you can see the window's support bracket bolts through the access holes in the door. Then disconnect the connector again.
Loosen the bolts on the support bracket with a wrench without removing them, and then lift the glass out the door through the top opening while tilting it upward at the rear.
Remove the mounting bolts for the window regulator and motor, disconnect the multi-plug from the regulator, unclip the regulator's cables and remove the regulator through the bottom hole in the door.
Slide the replacement regulator into the door through the bottom hole, bolt it in place and connect the multi-plug and cables.
Insert the glass down into the door, making sure it is correctly located in the support brackets, and tighten the bolts.
Reconnect the water shield, the door release, the speaker and the impact bolster.
Reinstall the door's inner trim panel.