A malfunctioning Toyota Tacoma tail light assembly should never be taken for granted. Any kind of failure in this component requires your immediate attention as it can result in a ticket or even an accident. So when you notice that your car's tail lights are not working as they should be, it's time to do a serious inspection to see what are causing these problems. Here's a simple guide on how to troubleshoot your tail light assembly.
If you noticed that a single tail light in your Toyota Tacoma's tail light assembly has stopped working, it could be caused by a burned out bulb. Remove the bulbs and examine it for broken filaments. You can access the tail lights behind the trim in your car's trunk. You might also have to remove the tail light lens cover to access the bulb. If one of the bulbs' filaments appears to be broken, you will have to replace the bulb immediately so you wouldn't have to drive with only one tail light working.
If multiple lights on your tail light assembly fail at once, this could be a sign of a blown fuse. Inspect the fuse by looking at the thin metal strip inside it to check if it's damaged. You can refer to your car's manual for the location of the fuse box if you can't find it. It also indicates the position of the tail light fuse. Sometimes, this problem may also be caused by broken filaments inside the bulb. Aside from that, overheating of the metal contacts at the bottom of the bulb may also be a possible culprit behind the failure of multiple lights in your tail light assembly.
If you have checked both the bulb and the fuse and none of them seem to be damaged, then it's time to take a look at your wiring system. Check your tail light assembly for damaged or loose wires. Make sure that all connections are solid and watch out for signs of corrosion in the internal surfaces.