I am very sorry to hear the Permobil F3 wheelchair is not functioning correctly. I sure know how frustrating that can be!
My answer is in two parts. First, I will discuss the need for and buying a backup wheelchair. Second, I will say a few words about the 20AA error.
Before buying a used wheelchair, be sure to check with the ALS Association. They often have loaner wheelchairs available.
My first wheelchair spent a LOT of time in the shop. There were no loaner wheelchairs available for me to use. I simply went without a wheelchair. I soon realized this was an unworkable situation.
I asked around to see what others had done and found that most eventually secure a backup wheelchair. The most common thing I heard was "if you need a wheelchair, you need two" (and I now have five
).
So, just a few months after getting my first wheelchair, I found myself looking around for a good used wheelchair. I decided to get the same brand and model (Permobil C500), but without the standing feature.
I found many wheelchairs on ebay and on craigslist. I am pretty mechanical and inquisitive, so I had already learned quite a bit about that wheelchair before considering buying a backup wheelchair. I bought a used wheelchair that was advertised both on ebay and craigslist. I talked to the seller by phone and decided to move forward with buying it.
The wheelchair was located 700 miles away, but in a part of the country my wife and I enjoy visiting. We drove there in our wheelchair van, inspected the wheelchair, and bought it. It has been my most reliable wheelchair (and I currently have 5 to choose from).
Used wheelchairs can be very inexpensive (relative to new) in the US. A new Permobil F5 wheelchair lists for around $50,000. I don't think anyone (including insurance) actually pays that amount, but that is the list price. A used F5 will go for about what many people's out of pocket costs would be for a new wheelchair. For example, I paid $3,500 for a used F5 with 226 miles on it. I also paid $800 for a used Permobil C350 with 26 miles on it.
Wheelchairs that have special adaptations for a user will cost much less on the used market. Both the used F5 and used C350 had custom seats on them. Fortunately, the Permobil Corpus 3G seating system is very easy to work with and it was quite straightforward to replace the custom seating components with stock Corpus 3G components. If bought new, those Permobil seating components are very expensive. Except for Upholstery, I buy things used off of ebay, which has saved me many thousands of dollars.
Here are the general rules I use for buying used wheelchairs
1. I will only buy a wheelchair I can see and ride in myself. I must be able to test the wheelchair to see what is working.
2. I will buy a wheelchair with things not working, but I must understand what it will take to fix those things.
3. I will only buy a low mileage wheelchair. I prefer wheelchairs with less than 50 miles on them. If I were to buy a higher mileage wheelchair, I would reduce my offer price by the cost of replacing motors and other wear items.
4. I assume I will need to replace all upholstery
5. I assume I will need to replace the batteries ($500 for a pair of good MK gel batteries)
6. I make a list of all the bits and pieces I will need to acquire to make the wheelchair fit me perfectly. I need lateral thoracic supports, lateral thigh supports, roho seat cushion, tall seat back shell and cushion, appropriate headrest, swing away joystick mount, good tires, etc.
7. I negotiate price based on what it will take to buy the wheelchair and get it perfectly configured for my use.
If you are buying a Permobil with a Corpus 3G seat, be aware that you may need to acquire an appropriately-sized seat plate and seat back shell so that the wheelchair fits correctly. Do not have him ride around in a wheelchair that does not fit correctly. It is not worth it!
As an example, when I bought the used Permobil F5, it had 226 miles on it. It had more miles on it than I wanted, but was priced appropriately for the miles. It had a custom seat on it and the headrest was not one I could use.
I paid $3,500 for the wheelchair. I spent an additional $1,500 to buy a seat plate, seat back shell, headrest, lateral thoracic supports, lateral thigh supports, seat back cushion and roho seat cushion. The upholstery was purchased new, but everything else was purchased from ebay. That wheelchair served me well until it was stolen (along with our wheelchair van) and destroyed by the thieves. Fortunately, I had backup wheelchairs so I could still get around.
Now, for the 20AA error. That is an error from Permobil's Intelligent Control System (ICS). This is the system that controls the seating component (power leg lift, tilt, recline, seat elevate, etc.).
The 20AA error means "Node is required but not present". That means it expects the tilt capability to be present, but cannot find it.
In my experience, the most likely cause of this error is a bad cable or connection. The ICS control panel is typically mounted just behind the joystick. Check the cable coming out of there and follow it all the way back to the master ICS module (on my F5 that is mounted under the shroud in the front left side [standing behind the chair and looking forward] of the wheelchair base). Make sure all connections are secure. Then, trace the wiring from there to the junction box (typically on the right side behind the unitrack rails on the side of the seat). From there, trace the wiring to the actuator that is not working. It might be the tilt actuator, but could be any of the other actuators.
Make sure each cable is intact and does not appear to have any internal damage. If you have a multimeter, you can check the continuity of the various wires in the cables. Make sure each connection is both clean and secure. Cleaning it with a deoxidizing electronic contact cleaner might be helpful.
If all of that is in order, then you might have a bad ICS master control module. I have had one fail, but with different symptoms than you report.
If you have more information about the failure, I will help as I can.
Despite the apparent complexities of modern wheelchairs, most are actually very simple (outside of the internals of the electrical control systems). There are very few black boxes and some cables that connect them. Most things on wheelchairs don't fail, and when they do are easily replaced.
Steve
