Hello, is anyone here familiar with these types of chairs?

The only name I could find was under the chair on a box, the name is Tranquil-ease. It was made around 91. I attached a pic, I hope it came through

I have a couple issues that may or may not be related. I actually wrote a big write up that got erased (so frustrating) so if someone here would like to give me some advice I'll post up the details.

I'm needing help understanding the weak links & trouble areas of the electrical system & the vibrator mechanisms. If your familiar with this kind of stuff maybe I could get this chair working again for my grandmother.

Thank you