Are there settings that allow mechanics to override the driving history / oil monitoring features of FSS?

My '99 E430 used to show a big difference between miles driven, and miles to next service according to FSS. That is, the FSS miles to next service would appropriately vary up and down as I drove my car between service intervals. The 10,000 mile initial value and subsequent readings would change to fit my driving and oil quality.

More recently, since I had my car serviced by another dealer, the FSS miles to next service reading seems to move in lockstep with miles driven. That is, after driving 3600 miles, it will say 6400 to next service...

I, being a suspicious sort, think that the servicing dealer may have changed the settings on FSS to NOT vary the reading based on driving style and oil quality, but to simply count down from 10,000 miles.

My current dealer says its not possible. Perhaps I just have too much time on my hands! In any case, if anyone has any knowledge, please advise; as I am left with the sense that my FSS is not monitoring anything.

Thanks!

I've never heard of this problem/comment before. I have never heard of the ability to configure FSS in this manner, either, nor can I think of a good reason why anyone would want to start messing with the settings on your car in this manner. I am going to review some of the printed matter at work and maybe there will be a similar FSS car I can go in and see what exactly you can change. Only a couple things come to mind, and that's the base mileage setting and the base time setting. I also know you can reset a FSS reset that was done in error, and today I had to change the mileage to the next service as I had forgotten to do it a month or 2 ago. But as far as changing the parameters for FSS calculation from oil quality/level and engine managment inputs and mileage and time, to a simle mileage countdown, that I've never heard of, but I'll check on Monday...Gilly