Hi June:)
I'm sorry to hear that your friend is having a lot of issues with there TDX 5:( I have had pole motor issues on a different model powerchair years ago and it was quite frustrating, so I can understand your frustration.
I guess if the user is driving through a lot of snow and water puddles it might be a good idea to look at a RWD powerchair as the Power module (brain of the chair which has plugs connecting to the motors) is higher off the ground than it is on the TDX Series.
The tech is right about the position of the Power Module placement on the TDX.
the service department advise me that the computer(0r whatever it is called) is at the bottom on the back of the chair and reacts to any moisture or condensation that might gather in that area...thus making the chair stop working.
From what you have said, it's not the design, it's the moisture that is the TDX 5 main problem as well as the recline operating on it's own after been cleaned.
Shame on Invacare for having a chair on the market at a very high price knowing that there are issues with the design.
When cleaning any powerchair, just wipe it over with a soapy wet cloth (dishwashing liquid is a good cleaner), having actual water sprayed on the chair is basically asking for trouble. If the wheels are needing cleaning via a hose, keep the water spray low and away from the plugs:) I know when I have to get mud off my wheels, I use a hose, but the hose is on very lightly and I have a brush nearby to help remove the mud. I also keep the water well away from the connections.
If out in the rain, cover the controller with plastic, I see the joystick controller is a MK6 MPJ so not many ways for water to get inside, but it is a good idea to cover it with plastic if wheeling in the rain. With any joystick controller, if water gets inside then it won't work anymore.
Just another thought is to avoid wheeling through 'big' water puddles, as that will surely wet some parts of the Power Module and connections. Try to avoid driving through 'soft' snow that creates the chair to sink in the snow as this will wet connections and that would be trouble too. If this isn't possible, maybe put some plastic or something covering underneath the power module so moisture doesn't get to the connections. Wheeling on firmer snow be better as the connections are higher off the snow. Just some ideas. I have never wheeled through snow myself so just thinking off the top of my head:)
I haven't yet 'touch wood' had any moisture problems and I have wheeled in the rain lots.
Maybe talk to Invacare about the moisture issues and explain that the person lives in a wet and snowy area which they will be wheeling on lots, and see if it's possible to replace the TDX 5 with one of there RWD powerchairs, Torque SP, Ranger or an Arrow.
Again I feel your frustrations and hope the above idea's might be helpful or replacing the chair, if that can be done.