@shirleylar63859 let's start off by clarifying what you have checked. Have you checked your battery? Have you checked your alternator? Use a voltmeter and measure the battery voltage between the positive and negative post. It should be around 12V Next, with your Passat running measure the voltage between the positive and negative post. What voltage do you get (expected is around 13.5V to 14V DC). If you have that voltage, it is most likely your battery. If you do not have that voltage, it could be your alternator. Let us know what you find out.