There are numerous light bulbs within your Ford Focus. In addition to the front and rear overhead lights, there are bulbs that illuminate the instrument cluster above the steering column and the controls within the dashboard instrument panel. These components each require different types of bulbs, so make sure you have the correct replacement bulb when you need to replace a burnt-out one.
Pry off the light assembly on the side opposite the light's switch using a screwdriver.
Disconnect the light's wiring connector and then unclip the reflector from the light unit by hand. Pull the bulb out of its socket.
Insert the replacement bulb, making sure the contact springs in the bulb holder have enough tension to firmly hold the bulbs.
Clip the reflector back in place within the light unit.
Reconnect the electrical connector to the light assembly and snap the assembly back in place within the vehicle.
Lower the steering column using the locking lever and then remove the column's upper shroud using a thin screwdriver to release the clips.
Disconnect the mounting screws for the instrument cluster's trim bezel, which are along the upper edge, using a screwdriver. Pull the cluster out and disconnect the electrical connectors behind it.
Twist the bulb holder in the instrument cluster counterclockwise to remove it from the cluster.
Install the replacement light bulb and bulb holder into the instrument cluster and twist it clockwise to secure it.
Install the instrument cluster back above the steering column, connecting the electrical connectors and screwing the trim panel bezel back in place.
Pry off the trim bezel for the instrument panel controls using a flat-bladed screwdriver or a trim stick.
Remove the mounting screws for the stereo and the heater/air conditioning controls, and then unclip and remove the units from inside the dashboard.
Remove the bulb holder from the rear of the unit by twisting it counterclockwise, then pull the bulb out of the holder.
Push the replacement bulb into the bulb holder and then install the bulb holder into the unit, turning the unit clockwise to lock it in place.
Slide each unit back into the dash, making sure their clips engage, and apply the mounting screws with your screwdriver. Clip the trim bezel back in place over the units.
Open the glove box and pry the light out of its opening using a small screwdriver.
Pull the light bulb out of the socket.
Install the replacement bulb by pushing it in.
Connect the light back into its holder.
Disconnect the car's negative battery cable from inside the engine compartment before removing any of the lights. Handle replacement bulbs with gloves to avoid getting natural oil on them, and make sure the bulbs are clean before installing them.