Permobil Smart Drive Battery Or Circuit Board Replacement

This is how to remove and replace a bad lithium-ion battery pack or circuit board on the Permobil (formerly Max Mobility) Smart Drive unit.
**NOTE** **WARNING**
This video is intended for technicians that don’t have experience or knowledge on how to work on a Smart Drive unit. Parts should only be ordered from Permobil by a vendor with an account and installed by a technician with similar repair experience on other power equipment.
Tools you'll need are:
multimeter to check basic DC voltage
3mm Allen “L” wrench or screwdriver
Torx T10 screwdriver
Torx T20 screwdriver
I would highly suggest you have a pillow, foam, shop rags, cardboard box or something to stabilize the Smart Drive while you are working on it while it's upside down, as you'll see in the video it flipped about three times and it gets annoying.
Did I make commentary mistakes? Yeah, but I don't make videos for a living so I don't have the practice. I really just make them to help others that may have a need for information or because as of the posting of my video there was no video showing a "How to" for the subject.
I know the Fenix 21700 says 5000mah and I said 500mah, whoops, my bad. have fun with it.
I've been a technician in the healthcare industry since 1992 and work on mobility equipment. My specialties are in complex power equipment and drive systems, complex seating and mobility solutions, programming, diagnostic troubleshooting, custom fabrication focusing on creating a solution for an individual need.
With that being said, I hope you enjoy the video and get some use from it. Feel free to leave comments and ideas.

[@kayware251]

Thank you my power drive seems to have burnt out 2 days ago going up a steep curb. I need to get it repaired ASAP. I’ve been a paraplegic for 31 years I have replaced parts on my chair myself. I need to find this battery and circuit board ASAP so I can continue going out independently.

[@shadowstorm7]

Contact your local authorized wheelchair vendor. They can get the part and install it for you. If they don't have a qualified tech then the local Permobil sales rep should be able to do it. They will not let you install the parts yourself. 👍

[@lunacyworks]

did you get your unit fixed? Where are you located, I am sure someone here can help you find a local to help.

[@zeeek1]

Mine just beeps when I push the hand switches to go forward. The main Battery voltage tests at 39VDC and the small tap you measure, measures 1 volt on mine. I have a ticket running at Permobil right now and if they don't warranty to main board I can buy one for about $100 I hope? I actually want to sell it, curious to it's worth second hand but no mileage

[@KristofferMay]

My smart drive is only showing “chasing” blue lights back and forth. They won’t stop until the battery dies after a few days! Is this the circuit board???? Pls help!

[@shadowstorm7]

Yes, does ot still charge when you plug it in? Another way to tell is if the wheel is hard to spin, that also shows if the board is shorted out. Did it get wet by chance or was it pushing more weight than itwas rated for?

[@thekalifornian5504]

@@shadowstorm7 needs a new circuit board...:(. is there a place i can find that reliably? otherwise i have to gamble with ebay sales

[@shadowstorm7]

@@thekalifornian5504 Sadly, no. Permobil keeps a tight hold on these and the only way to have them replaced is through a certified dealer. Ebay is a gamble as you mentioned if that's the route you have to take. I would suggest trying to have health insurance pay for the repair if possible. Best of luck.

[@zeeek1]

If that's a 3 wire motor connector then if it''s [plugged in backwards the motor will spin backwards.

[@shadowstorm7]

It is a 3 wire connector. The connector is keyed only plug in the correct way for forward motion. Only parts directly from Permobil should be used. However to answer your question, here is a great video about brushless motors. kzbin.info/www/bejne/d4Kocnt7r8aIgKc

[@pablocasanova2386]

Are there any authorized wheelchair vendors you can recomend to me? I understand from the comments that I can also buy the battery or/and the circuit board from them?? I believe my battery and circuit board need replacement.

[@shadowstorm7]

You can do a google maps search for local wheelchair providers/shops near you. Select one that looks like they know what they're doing and call them to see if they have an active account with them and can order you what you need.

[@shadowstorm7]

I'm in the United States, so if you're not you might need to contact Permobil directly and ask them for a list of providers that can help you. I have one guy that lives in Costa Rica and he will stop by when he is visiting his family in the States or his family will pick up parts when they will go visit him.

[@bluecaka69]

How did you get new battery?? My daughters went out and I was thinking of rebuilding the pack but buying new one would be easier

[@shadowstorm7]

Buying a new battery would be the best way to go. They're not cheap. Like $1300. The reason rebuilding the pack isn't a good option is because there are so many wires to solder and make sure are connected correctly. It has a battery managment system wired in as well to make sure the individual cells are charged and balanced. I've been working on chairs since 1992 and also work on RC planes and other electronics. Even I wouldn't want to do it unless I absolutely was forced to.

[@bluecaka69]

@@shadowstorm7 I called permobile today and they won’t even sell a battery they want like 2200 and I have to ship it to them so they can swap batteries.. pretty pissed at the whole thing.. I might try to jump start the battery pack to add some voltage to see if it will start taking charge

[@shadowstorm7]

@@bluecaka69 well if you need to go that route you will need three 12 volt batteries. Wire them in SERIES to get 36 volts at the positive and negative post. Then you need to wire that bank IN PARALLEL to the smart drive battery. Leave it connected overnight so the larger 36 volt bank equalizes (charges) the smaller 36 volt smart drive battery. You might get some use out of the smart drive battery but it may never maintain it's specified capacity and run time because the battery wasn't maintained properly. That's what happens when it's left to sit too long without getting charged.

[@bluecaka69]

@@shadowstorm7 awesome thanks I’ll update you if it works

[@shadowstorm7]

*** UPDATE *** This may not work if the battery pack is severely discharged. Never leave the pack unattended during a process like this. Monitor voltages and disconnect if it seems anything is getting too hot. Again, trying to balance / charge the battery this way can go wrong nad is really not recommended.

[@chuckgaudette8885]

Your video is very clear and I should be able to replace my battery. Is there somewhere to get a new battery that doesn't cost $1300? Like everything else for wheelchairs its way overpriced.

[@shadowstorm7]

Sadly the only place I know is from Permobil. I don't think they will sell a battery directly, they will have you buy it through a local dealer. The only discount would be given by the dealer, not through Permobil. Hope this helps clear your question up.

[@chuckgaudette8885]

@@shadowstorm7 thanks for your reply. I don't know exactly what is happening with my battery. After 12 hours it will charge to 70% with 3 lights. Then after sitting off the charger for a day or two it shows 97% charged. Maybe a loose battery cell connection or something.

[@shadowstorm7]

You can check those connections. I had one client that actually had a loose connection, probably due to dropping the unit and bad factory building.

[@chuckgaudette8885]

@@shadowstorm7 Thanks for your comments. After thinking about it, the battery couldn't have gained 30% charge by just sitting. So I'm thinking the battery was fully charged all along and the problem is the circuit that indicates the amount of charge the battery has is the problem. What do you think?

[@shadowstorm7]

@@chuckgaudette8885 there are four corresponding blue lights near the power switch. Those will show state of charge; 100, 75, 50, 25 percent respectively depending on how many are lit. An alternative would be to verify this through the bluetooth connected Push Tracker, it will also be able to display the level of charge in the drive unit.

[@jessiec4128]

The price for that battery pack is very expensive. I checked at I can not afford to repair mine. My battery is the problem. My curcuit board is fine.

[@shadowstorm7]

If you were able to get it through medical insurance you should also be able to have it maintained through that insurance.