[plymjack]

The only items of servicing for a BEV i3 are to change the cabin air filter and to change the brake fluid (both every 2 years) - all other items are as needed eg brakes & tyres.
Other items are inspection items carried out as part of MOT or visual inspection.

If you carry these items out yourself this is how to reset the reminder (tested today)

1. Hit the on/off button without pressing the brake (should be in accessory mode)
2. Press and hold the trip odo reset button for ~10 sec. The display will say "reset possible"
3. Quick press the trip odo button to scroll through to whatever needs resetting
4. Long press the trip odo button; it'll say something like "reset?" Long press again to confirm

Hope it helps someone... an BEV i3 becomes very cost effective when you save on servicing costs.