Cruise control downshift.

[yellowhillman]

Hi there. I have a 200 C220cdi with tiptronic box. Recently,when driving on motorways, it has started changing down after I have accelerated with the cruise control on.Any ideas would be much appreciated.

 

[brucemillar]

My C55 & C240 will automatically change gear(s) with Cruise control on. This hapens if I am on a steepish hill. Can't say I have noticed on a flat road.

 

[tode]

That seems normal, as long as revs stay between 1500 -2500. Should change back up when you resume cruising.

 

[mersum1es]

And cruise will stay on even you change gears with tiptronic.

 

[yellowhillman]

Thanks for the replies. I'm used to it happening on a steep decline but this is happening on a normal motorway level and it always happens after I've accelerated whilst the CC is on. I lift off after passing and it changes down to fourth gear. I understand that the box does change down in some situations to help with engine breaking but this gear change after acceleration is a new one on me. I've had the car for four years now and it didn't used to happen.

 

[baz towler]

might be barking up the wrong tree I had this prob last year E 320cdi tip had the ATF fluid changed and prob was solved. bazboy