The negative cable, which is normally connected to the negative pole of the battery, is fastened to the crankcase. From here, the cable branches off and splits up within the electrical system to carry the ground connection to the different elements in the system.

The image shows the ground connection on left side of the engine crankcase.
The battery charging circuit and power distribution
Electrical power for lighting and signalling devicesLcd unit functions
Speedometer.
Gives road speed.
Rev counter.
Indicates engine revs per minute.
Clock.
Water temperature indicator.
Indicates engine coolant temperature.
Important
Stop riding if the temperature reaches the maximum
value, otherwise the engine might be damaged.
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Symbols
Ducati motor holding s.P.A. Advises you to read this manual
carefully in order to become familiar with your motorcycle. If
in doubt, please contact a ducati dealer or authorised
service centre. The information contained herein will prove
useful on your trips - and ducati motor holding s.P.A. Wis ...
Replacing the battery in the active key
Only use 3 volt cr 2032 lithium ion batteries.
Note
The keys do not need to be reprogrammed after
replacing the battery.
Remove the metal part of the battery.
Use a large sized coin to pry open the shells of the plastic grip
(2? coin) as shown in fig. 65.
Important
Insert the coil on ...