Citroen Cactus Diagnostic Equipment

[MikeyMike]

My better half's Citroen Cactus has reached the end of its 3 year warranty period and I plan to start servicing the car myself. Whilst I'm a dab-hand with a set of spanners my cars have always been of a vintage where diagnostic tools/readers etc haven't been required. Can anyone point me in the direction of what equipment I might need in order to read error codes/reset the service indicator etc?

Thanks