mileage is still stored in ecu on these vehicles , had a customer 2 years ago who bought a sclass he had problems with dash warning lights , i took dash out and found unit behind clocks just plugs in. he asked for it to be removed and the mileage stayed the same. when he took it to mercedes he asked for them to check the mileage bearing in mind what i found and withing 30 mins they gave him a printout of the true mileage of the vehicle .
it was just under 30k higher than it was displaying. after going back to the garage that sold it him he received compensation from them , and returned the vehicle to mercedes who did a software upgrade and the true mileage reappeared. he was a happy bunny again.
these units only deceive people looking at the displayed mileage.
as i said in another thread if you look close enough with diagnostic equipment you can find all the gremlins, most modern cars log mileage whenever there is a fault and in most electronic units.
as to the focus ford has a policy of not altering the mileage on any new clocks they fit had loads of folk on the galaxy forums with the same problems.
when you pick up your new car from v/w make sure it was supplied on a transporter........because there diagnostic equipment allows them to reset the mileage to zero, 3 times providing it doesnt exceed 99 miles per session...been there and seen it done .
on other extremes peugeot had a problem with 406/407/206/207/307 models where they would add mileage at random i even watched a watchdog program where they confronted peugeot about it.
at the time we had a contract to fit reversing sensors and insurance aftermarket alarms for a few local dealers. remember one particularly nice brand new 307cab still in pre delivery grease we were working on, in 2 hours we had it we did 123 miles in it. even showed the salesman
everytime you opened the door and the dash lit up it increased the mileage by 3 or 4 miles. he just said it would be delivery mileage and past it off as this made me very wary after that.
