Ever notice a single bulb that burns out often?
The 4th generation Mirage tail lights have a few grounding issues. Here are some pictures showing where to look and how to fix them.
This may also affect other models.
Check to make sure the main grounds are screwed down tight and not corroded.
If the ground is corroded or rusted, sand it down as clean as you can get it. If necessary, add a second ground and tap it into the existing grounds. One of the other issues is that the grounding point is painted and only has a connection through the screw threads. Sanding down the paint under the screw will provide a better connection and you can put some dielectric grease on it to prevent rust.
Disconnect the plug from the taillight. At the bottom of the bulb "housing" there are two tabs you push up to release the whole bulb plate. Flip it over and move on to the next image.
Notice the light bulb holders are held in place on one side by a plastic tab and the other side by a single screw. This screw also holds the grounding wire against the bulb holder. Half the time they are not tight from the factory. This causes a bad ground, which causes heat, which causes corrosion and melts the plastic it is mounted to. Eventually, the bulb will burn out from the bad ground and the screw will get hot enough to melt out of the bulb housing.
Notice the one on the upper-left that has a small bolt though it. The plastic was melted so bad that I can not attach the ground by the OEM method. I used a nut and bolt to hold the ground onto this bulb. The next picture shows a close up of how the design is supposed to work and should give you an idea of why it doesn't work very well. The plastic isn't strong enough for the factory to just crank down, so many hit the screws torque spec before bottoming out on the ground wire. Move to the next picture.
This is the main failure point. Check to make sure all of your grounds are clean and tight!