When pressing the winter summer button it gives an ESP cod and the transmission will go in to revers and drive but doesnt gear up or chance gears on the tiptronic. 2001 Mercedes-Benz c270 cdi

With the engine running and the clutch pressed all the way down try each gear in turn and listen. Do you get any crunching or grinding noises? Nasty noises on gear changes with the clutch fully pressed is commonly a sign of a badly worn clutch. No noises suggests linkage problems or an issue inside the transmission itself.
On a manual transmission you start at the gear stick and work down to the actual transmission. First check the links on the gearstick under the floor. Then follow those cables down to the transmission and check the linkages at that end. Sometimes a worn or loose linkage bush can cause loss of gears. Next check the arms and levers on the outside of the transmission itself. Work it by hand feeling and listening for it "Clunking" as it drops into all the gears. If it doesnt feel solid and 'notchy' the issue could be inside the transmission itself. You'll need a gearbox specialist to look at it for that issue.

The transmission has failed.

It because of the forks inside the transmission are worn out or they have lost their plastic pieces on the fork ends.(some transmissions are built this way, plastic). you have to pull the transmission to fix it.

sorry jhbkane. ur solution doesnt work..i hav change my this ECU several times but still it dont work in winters...

And alibaba69: i hear this taka taka sound n my pajero mini sometimes when the gear shifts..i have placed a new fuel pump but still its there...Wots this..?? any suggestion plx

Have you had the transmission control module scanned for fault codes? This transmission is electronically controlled. If no codes show up in memory then you may have a mechanical problem, Also winter selection starts in 2nd gear, so you may be missing that gear.

I believe the winter power button makes it so your truck starts in 2nd gear instead of 1st gear to reduce slipping and gain traction... It might do other things with 4 wheel drive. The whole point is to give you a better chance in the snow,

The winter drive button gears the transmission down so that it doesn’t spin when you take off from a dead stop in the snow and ice. It only activates by pressing and holding it when at a stop and then accelerating.

Power is for when you are hauling heavy loads. It holds a higher rpm before shifting to next gear giving you best hauling performance.

Hi,It might be worth giving your autobox a ((complete)) newATF fluid transplant approx 7ltrs ,but to be honest it sounds like you have major gearbox failure (valve block seals/springs/valves,etc)not a cost effective repair,cheaper to replace with another autobox.

transmission fluid low???? check when it is hot also do you have a revers band adjustment on this???model