Usually try to find the answer myself in manuals or elsewhere on the internet, but this one has truly stumped me since yesterday. 
Was doing my usual Saturday shift on the agency. I don’t find the digi too difficult a beast to grasp usually and can do the basic functions I need to. I also have my truck timer app as a back up to monitor what my times are adding up too, as I do multi-drop.
Now I know I’ve been off the lorries since 2009 and have come back to it this October again as a hobby. But I like to think I have an avid interest in things to do with the industry and the curiosity to learn how to do things right.
However, I don’t know who the hell to ask on this question, the usual suspects are unable to help me unfortunately (like my Dad etc), so out to the forum it goes.
I was using a Seimens VDO not sure what version or how to tell off the printout?? 
However my main problem was in this particular MAN. When I started first thing in the morning and did my pre-check start up it was on rest setting as soon as card correctly inserted and registered turned the setting to other work. This next statement will become important later on!
Left ignition key in and done my pre-checks. 20 minutes later, jumped in the seat, left the bay and yard, so automatically onto driving mode. When I stopped at first set of traffic lights realised it had switched to rest again when we was stationary■■? Shouldn’t have done as it was on other work mode when we left the yard! Lights turned green ignored it.
Porter wanted a take away so pulled over and let him go on his merry way. Happened to look up at the tacho head unit as I had turned the ignition off, only had side lights and hazards on and the bloody thing had gone onto rest mode again! So I turned it over onto other work again with the the ignition on “pre-ignition/diagnositc checks” and waited for porter to come back.
So again it was on other work mode when we pulled away safely and headed off into Norfolk. 1 hour and 40 minutes later we got to our first drop. Stopped the lorry, turned the tacho over to other work again, not really noticing it had zbing changed to rest mode when we had stopped again! I was 100% sure it was on other work before I got out, took the keys out of the ignition, locked the cab and helped porter unload. On my return before I pulled away looked at the tacho head and rest mode was showing but thought it must have just changed to that and had been recording other work correctly seconds before then 
Not so!
Done this pre-unloading routine three times, before I realised looking at the truck dashboard it had told me that I had done x amount of driving and over 50 minutes of rest already, when I clearly hadn’t physically in reality and the time should have been other work!
Getting concerned now I wouldn’t be paid properly as any minutes on break we don’t get paid and this was racking up loads especially as we had 15 drops to do!
Done a printoff halfway through delivery route schedule at my 45 minute break and looked down through the printoff and all the tacho was recording was bloody “rest” mode when it zbing should have been “other work” mode.
On the last three drops of the afternoon, they were all store “lock-ins” so I left the keys in the ignition whilst unloading and the tacho then recorded “other work” as selected. However the disadvantage was this couldn’t be done on the public deliveries for obvious reasons!!
Contacted my agency for advice, as we had a non-driving operations senior manager in that day who wouldn’t have had a clue what I was talking about. (He doesn’t even do the downloads at the end of the day “kind of guy”). They said do my suggestion (print off two copies and do a manual trace, give one to office, keep one for myself and scan a copy in to send to agency office in case of any wage discrepancies).
Luckily by the time we got back in the evening the usual TM was in. I explained the problem to him, he didn’t know what I was doing wrong, but could see what was happening from my card once it was downloaded. He could see I had only one legitimate correct break that day my 45 minute one! And the other rest/breaks recorded should have actually been other work. He said he’d make sure that my time sheet would be amended corrected to only show the one 45 minute break and everything else would be other work and my pay would be correct.
My question, is what was I doing wrong when selecting the modes■■?
At the depot I work at we have Renault’s, Scania’s, DAF’s and MAN’s all of which I have driven now since I have been there and all have Siemen’s VDO’s in them. I have never had this problem before and how I select modes hasn’t changed in my eyes. Every other time I’ve set a tacho to other work on the other vehicles and unloaded its remained on that setting until I’ve wanted to change it, not changed the settings how it wants too whilst the vehicle is stationary!
Hope someone can help point me in the right direction of where I am going wrong and correct my lack of intelligence on what is more than likley a simple problem! 
Thanks in advance for your help.
C
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