1. Remove the two side panels. (8 screws)
2. Remove the four screws that hold the top on! Two at the front, two at the rear.
3. Undo the two wire (red/black) plug nearest the edge. It stops you taking the top off. TAKE NOTE WHERE IT COMES FROM! There are two places it can go back, one is wrong, and will not work. (on some boards only)
4. Take out the thin plastic ribbon. The place it is inserted has a locking collar! Don't just yank it out! Lift the top edge/lip of the black socket with a finger nail and the cable ribbon will practically fall out. Same when you replace it. Lock it after you insert the cable. This is actually the control buttons connection on top cover.
5. remove the white multi plug with care. It cant go back wrong so don't worry. This is the display connector.
6. Lift off the top, and leave the big fat power cables connected. Lay it upside down on the other side out of your way.
Look at your new Serial Bluetooth adapter. It will have 4 wires:
LARGE IMAGE HERE WITH CONNECTION POINTS MARKED!
Obviously the POS needs power in this case from the rearmost gold pin on the TEMP sensor port. And the NEG needs a negative! This comes from the base of the USB connector. See later pictures.
THE BT (BLUETOOTH SERIAL DATA) BOARD:
There are two here. 2 boards, and two plug on cables. You need just one obviously... Shown here both ways up.
First TIN the BT board wires...
Then attach them to the 4 points shown on the photos above and below... These points are the same on the 1420, and the 720.
If I can do this with 50 year old eyes, sat in a wheelchair, with a big 35 watt soldering iron and shaky hands it cant be that hard! And this was the first one. The other two are much neater! Looks worse than it is, because these parts are really small, the photo is a "close up" so looks bigger than real life.
Above shows the wires soldered, and the board sat waiting to be attached to the INSIDE of the drilled side plate /cover! As shown below.
Drill a 3mm hole in the side case as shown here. Use a bit of double sided foam tape to attach the new BT board to the side - inside the case so that its built in LED lines up with the hole. And re attach the side.
This flashes when the charger is powered up, and goes solid red once it has established an automatic connection with your PC or Laptop. Very useful to be able to see this! And these boards have only about 30 feet (10 metres) of range. So sitting the new board flat against the outside edge maximises range, and connectivity. But in a noisy environment you may get considerably less. So this is important!
(ADDED) 730i CONNECTIONS BELOW:
More info and pictures on my forum here for some DUO chargers like the 7201 620i etc
Range... Get a 100 meters range Bluetooth Dongle for your PC. The common small micro USB Bluetooth adapters will give connection/range problems, well mine did! Some are rated at 10 meters and do less - you will wonder what's going wrong! Ask me how I know...
SOME on my batteries! I charge this 72Ah 13s 6p LiFe pack, as well as the usual AA, AAA, LiPo, Nikon camera lithium Ion, strimmer, mower, and two wheelchairs with 2x 70 Ah lead batteries very regularly! At home and in my car.
Forum discussion for those that cant get it to connect, its usually a Bluetooth setting in windows... http://www.wheelchairdriver.com/board/viewtopic.php?f=2&t=1785&st=0&sk=t&sd=a