Q: I have a 2012 VW Jetta SE and I was pulled over and the cop told me both my brake lights wernt working. So I bought some bulbs and

It sounds like you may have a weak battery, a failing voltage regulator or failing alternator. As you may know, the alternator charges the battery while the engine runs by generating amperage and recharging the battery while the engine turns the alternator pulley. The voltage regulator is a unit that regulates the charging of the battery by the alternator and maintaining a certain amperage while the engine runs. When the alternator is not working properly, this may result in the battery quickly losing charge, the car losing power or in some cases, causing fluctuations in various electrical components as you have described. You may also notice a whining sound as a result of the bearings inside the alternator begin to fail. I would recommend having an expert from YourMechanic come to your location to diagnose and inspect your charging system.