The 2 connections provided are of the Plug and Play type: you will find these 2 plugs above the sprocket at the height of the speed sensor on the gearbox.
For the adjustment you must open the unit case: you will find a small switch and a mini LED screen.
1 -Press switch and switch on the ignition.
2-The letter F is displayed on the screen: if it is not the case it is because the box is badly connected.
3 -F = adjustment of the front gear. By pressing quickly you can change the size of the sprocket from 1 to 10 and a long press to go to unit from 1 to 9. The box is saved by default with 1 and 5 = 15 teeth. By pressing slowly you will go to next step.
4-R = if the previous setting went well you will see the letter R (A) it is the setting of the size of the rear sprocket, by default it is on 3 – 4 (for 34 Tooth)
5-r: if the previous setting went well you will see the letter r
it is another choice of optional setting but it is mandatory to go through for saving what you entered.
Here you can adjust the percentage change. So if you want to do it directly via the number of teeth on the sprocket not change anything here -1-0-0 = 100%
If however you wish to change the indicated ratio without encoding the gears and sprockets, do not touch the previous settings (15/34) and change the here. In the same way that the gears you can enter the percentage of change for the meter indicates the correct speed.
This is for exemple if you change tires dimensions : 120/80 x 12 is 103% or 120/70 x 12 = 96% etc…
6-F: you MUST arrive here and have the F appear again: otherwise the previous data will not be kept. WAIT 4 seconds and you can switch off : all is saved.