My diagnosis would definitely lean towards Remitting/Relapsing MS, as the majority of problems I've encountered are intermittent making it difficult if not impossible for the technical staff to pinpoint the exact cause in addition as you can tell from the photograph it looks brand-new so there can't be anything wrong can there? I mean "you look so good."
Other than a flat tire which is quite evident requiring little if any technical knowledge a no-brainer really problems which surfaced a few years after receiving the chair have for the most part been intermittent.
One of the first problems I encountered took close to 1 1/2 years to resolve. I would be riding along and all of a sudden the chair would come to an immediate stop. Lights on the joystick control module would flash intermittently and once in a while I would hear a faint beep. In some cases it was simply a matter of pressing the on button located on the joystick resetting the speed setting and away I went. At other times I could be sitting there for 45 minutes pressing the button to no avail when suddenly it would once again come to life. The problem was of course due to the wiring circuit a short basically again mimicking MS, it was decided the joystick as a whole should be replaced unfortunately while it appeared to have cured the problem while I was at the repair center, possibly "The Placebo Effect" soon after leaving the shop I began experiencing the same problem.
It got to the point where I was so tired of bringing it in I lived with its intermittent operation for over a year. Finally after voicing my dissatisfaction a meeting was scheduled with the Pride Rep. He recommended a complete wiring harness replacement and possibly replacement of the control modulator based on the chairs age and the fact no one really knew what was the cause of the intermittent stop and go problem. After the harness was replaced I had to request that the control modulator be replaced as well, from a technician's perspective replacing one part at a time would make identifying the responsible part of whole lot easier replacing both the harness and the control modulator would make it next to impossible unless they were installed in another chair and tested. At this point however I must admit I wasn't thinking as a technician I was thinking as a customer I needed the damn thing fixed.
There is nothing like crossing a busy street at an intersection and having your chair all of a sudden decide to stop in the middle of the intersection! Unfortunately most drivers don't really give a hoot ,once that light turns green you feel like a sitting duck actually you are a sitting duck! Luckily nothing ever happened yet that's what pushed me over the edge making me more persistent with the repair staff.
After getting the wiring harness and modulator replaced this problem was fixed once and for all.
My chair is fitted with a tilt mechanism which seems to have a mind of its own. When it totally broke down several weeks ago requiring the main motor to be replaced, again a no-brainer when you see mechanisms which are broken it's easy to identify the necessary repairs. A week or so later whenever I activated the tilt mechanism not only did it tilt backwards at one point it would tilt sideways which was awkward and scary at least the first time. Again an appointment was made to bring it in for repair the next day. That evening my spouse found a piece of my wheelchair on the floor and asked me what it was? Didn't have a clue yet once the technician saw it well it also turned into an easy fix. When you have a part in hand there is no guesswork involved, another problem solved.
Since Friday it appears we're back to some intermittent electrical problem of sorts.
There is no problem tilting the chair the problem lies when trying to reposition the chair i.e. lowering the lift mechanism. Again controlled by the joystick when I move it to lower the chair it makes a clicking noise and the chair lowers an eighth of an inch or so. It can take a long time to go from a fully tilted position to a normal one, just got off the phone with a technician they will be calling me back to schedule an appointment yet I've been forewarned it's difficult to find an intermittent problem and God don't I know it.