Sounds like you have found the problem, connect an amp meter in series with the battery lead and battery and see what it reads, if its more than 100 ma ( tenth of an amp) you have a problem and need an auto electrician. If you want to faultfind it your self, pull one fuse at a time until you see the current drop then check the manual to see what it feeds.

Not to familier with these 'modern' vehicles but I would have thought that the alarm could be switched off or disconnected. You should be able to cancel it once the meter is in circuit but you will initially have to set the meter to a higher range.

Slacken the earth clamp and secure the meter probes, one to the clamp and the other to the battery terminal, it takes two people as tyou now need to lock the car and let the sytems shut down now lift the clump up and take the reading. Remember the alarm also takes time to set properly, 30 secs or so. Beware you may have bonnet switch associates to the alarm. Regards Peter

Some cars illuminate the oddometer for 30 secs after the ignition goes off and also illuminates if a door is opened ( including the bonnet ). Regards Peter

This could be a faulty relay for the instrument panel all being well. Regards Peter