why is the vibrate feature not working on my phone?

[sb6918]

The vibrate feature is broken on my phone. I have the LG Extravert 2 Phone, model number LGVN280. Does anyone know what could cause the vibrate feature to break on this phone and how I can fix it and get it working again. I did a factory rest on the phone and it didn't fix the problem. If anyone can give me details in wording on how to fix it so i don't have to send it to a manufacturer to fix it that would be nice. Let me know what tools i need yo fix so I can do it myself and not have to send it to a manufacturer. My phone is out of warranty and the price would be too expensive to send it to a manufacturer. I want to know how to fix it on my own for free. I would use the exact operations like a manufacturer but just needs to know what tools I have to have to fix it.@