You NEED to spend time and study the manuals or workshop manuals if possible of powerchairs, breathing equipment, accessibility equipment and your vehicle too!

My own van and powerchair for example has failed on a number of occasions. But knowing how and why it worked in every tiny detail allowed me to fix or remedy the situation one way or another and saved me from getting stuck in a strange town at 2 am.

If you know something can fail like a tyre, you can take suitable precautions. Your car should have at the very least a can of puncture "fix" aerosol.

But more importantly you should know the jacking points and the jack location and where the wheel brace and any locking nut adapter are!

Have a look now to make sure they are present and the spare  tyre is inflated You may need to tell anyone that can help you. Be responsible. Better still get a set of these  Or at least get your powerchair and your car/van tyres filled with this tyre puncture proofing stuff before you need it

A battery connection or plug and socket? You can fix it if you know where they are and what they do. Learn things like error codes that your cars dash can display,

If you have read all the books and handbooks you will have a good clue why your device isn't behaving as it should. If you still don't know what something does then unplug it and see what happens while at home in safety! Learn how your adaptive systems work in detail a home in the warm and the dry. When you break down at night in the rain and cold is a bad time to realise you need a fuse for xyz to get home.

Or even a computer crash (there's one in the luggage compartment that controls the automated door/ramp/lowering systems on my van) and you can reset it. It wouldn't let me in!

The ramp and door were all out of sequence. The book tells you what all the error codes and beeps mean. It let me in and got me home after it failed late at night because the information I needed to fix it was already in my head!