C180 distronic does not downshift to maintain speed
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A205 C180 & R170 200K
C180 distronic does not downshift to maintain speed
When I drive on the European highway, set my DISTRONIC PLUS to >90 mph or more and encounter a long uphill section, the car struggles to maintain the set speed in the 9th gear and eventually slows down to <80 mph without downshifting.
When I downshift manually, there's no problem and the car maintans/returns to the preset speed. I suspect this won't be a problem for larger engines because they have enough power to maintain the speed in the 9th.
Does this happen to anyone else? Shouldn't the car be able to downshift automatically when it starts slowing down? It has no problem doing it for reasons other than lack of power...
When I downshift manually, there's no problem and the car maintans/returns to the preset speed. I suspect this won't be a problem for larger engines because they have enough power to maintain the speed in the 9th.
Does this happen to anyone else? Shouldn't the car be able to downshift automatically when it starts slowing down? It has no problem doing it for reasons other than lack of power...
Thread Starter
Newbie
Joined: Sep 2018
Posts: 9
Likes: 0
A205 C180 & R170 200K
At this speed it's still above 2000 rpm, so there's no vibration or anything, it's just going full throttle and decelerates because it doesn't have enough power. As soon as the slope eases it starts to pick up speed again.
I also forgot to mention that it's been this way since the car was new and there are no stored faults or anything - authorized dealer inspected the car, updated all software, downloaded data from various ECUs.. all seems OK.
I also forgot to mention that it's been this way since the car was new and there are no stored faults or anything - authorized dealer inspected the car, updated all software, downloaded data from various ECUs.. all seems OK.
Last edited by face404; Oct 21, 2021 at 11:59 AM.
MBWorld God!
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At this speed it's still above 2000 rpm, so there's no vibration or anything, it's just going full throttle and decelerates because it doesn't have enough power. As soon as the slope eases it starts to pick up speed again.
I also forgot to mention that it's been this way since the car was new and there are no stored faults or anything - authorized dealer inspected the car, updated all software, downloaded data from various ECUs.. all seems OK.
I also forgot to mention that it's been this way since the car was new and there are no stored faults or anything - authorized dealer inspected the car, updated all software, downloaded data from various ECUs.. all seems OK.
What I could suggest doing is to ask your dealership do a manual transmission adaptation depending on the speed of the vehicle and the current RPM. I hope they are able to assist you with that.
