W211 Clock and trip computer not working since Battery change
I have swapped out both batteries on my W211 Merc after getting the Convenience functions temporarily disabled after a cold winter on cold starts - those problems have since cleared
However since doing the battery changeover - the analogue clock on the dash has frozen to the time I disconnected the batteries - and the trip computer (the one next to the KM/H static readout) - always resets back to 25.5 miles when I come back to the car. If I start a journey and reset the trip computer using the button - it reads 0.0 but does not go up at all during the journey..... and will always reset back to 25.5 after locking up and coming back
Somethings obviously gone a bit crazy - the COMAND Time is set correctly and GPS is picking up the time and the date. Disconnecting both batteries for an hour and resetting does the same - analogue clock still frozen and trip back to 25.5miles
Anyone have any ideas? On my instrument cluster theres no option for Time sync or anything like that as per other posts I've seen.
Panicking now that I've got a shagged front SAM unit or something. Everything was fine before the battery change.
In other news - my issues still exist - time is frozen and the trip computer still reads 0.0 or 25.5 after another battery reset. There is another problem too - the actual ODOMETER is frozen. My mileage does not go up during driving. The trip computer that gives you MPG after reset / after start works correctly though....?!!?!?!

It's going into the dealer for an A service next week and they have been informed of the issue and will plug it into DAS to see what they can find. The Assyst+ data is also frozen - the mileage isnt counting down on the days remaining
I would hope it's not the SAM modules or anything of that given that the only fault is the Odometer being static and the clock being stuck.
Cheers for your advice - I'll be sure to let everyone know what the outcome is.
It's going into the dealer on Tuesday for an A Service and they will look into the issue as they agree that a battery replacement on an 8 year old vehicle shouldn't require the assistance of a dealer
The fault looks to be confined to the central gateway - the COMAND diagnostics menu is also reporting the same static mileage as the dashboard (but in Kilometers) - and also pulling the fuse for the central gateway and putting it back in causes the trip computer to reset to 25.5 miles again.



