ODOMETER JUMPS FORWARD 2003 S500-4m

[Rich126]

It's been a while since I've posted, but hopefully someone can help me.

I bought at 2003 S500 in March-07 with 27k miles. Car had 29k in June and the odometer jumped forward by approxiamtely 3k miles to 32k inside a 25 mile trip. I brought it to the dealer who checked and basically said that everything was fine, and the problem I described was impossible and I must have been mistaken. After a week and half of fighting about it, I gave up and took the car back.

30 days and 1000k miles of usage elapses with no problem, until Friday 8/17 when odometer jumps from reading 33k to 36k.

Then, Saturday 8/18 2PM odometer jumps from 36k to 40k. I break out the digitcal camera and determine the artificial increase is 4056 miles. This is based on the cluster screen entitled "AFTER START" and bymultiplying average speed by avg miles per hour, arriving at an actual distance traveled, and subtracting such from the number of miles traveled as per the cluster. (See photos)

Saturday 8/18 10 PM odometer jumps from 40k to 44k. 4056 increment again.
Saturday 8/18 11 PM odometer jupms from 44k to 48k. 4056 increment again.

Note the mileage "AFTER START" v. the time elapsed which evidences some sort of problem.

The car is back at the dealer with 48k and I'm being told they have never heard of this before, and they the car reads no error codes. Thhe service manager has been driving it to and from his home and the problem has not resurfaced. They don't dispute that something's wrong, but at the same time, won't fix it until they can witness a jump in mileage themselves. I spoke with the regional engineer from the manufacturer who covers the dealerships in the area, and he states that he has never heard of this before.

Hopefully someone can offer some advice.