trans down shifts by itself ?
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MBWorld Fanatic!
Joined: Aug 2008
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Porsche guy who drives SL63 w/ perf pkg AND perf suspension
trans down shifts by itself ?
I use my paddles alot, almost every time I slow down. Last night I went up on the interstate and was driving 50 to 70 mph. It was in C comfort. It was in 7 and went to 3 on its own. I up shifted and got it going. Then it started downshifting multiple times in all different gears. I feel that the down paddle was stuck.
It wasnt flexable like the up paddle. It did the same downshifting when I put it in S and M and C. The up would respond but it would still start downshifting no matter what I did to it. I let it sit all nite. The down paddle feels normal. So I took it out today and drove a few miles, in C with no paddles at all. It went perfect.
I know it could be in the trans control, but Im feeling like it may be the down paddle. When I was shifting, I think it may be stuck down. And then that gives constant or intermittent downs to the control module.
Any one with experience with this.
It wasnt flexable like the up paddle. It did the same downshifting when I put it in S and M and C. The up would respond but it would still start downshifting no matter what I did to it. I let it sit all nite. The down paddle feels normal. So I took it out today and drove a few miles, in C with no paddles at all. It went perfect.
I know it could be in the trans control, but Im feeling like it may be the down paddle. When I was shifting, I think it may be stuck down. And then that gives constant or intermittent downs to the control module.
Any one with experience with this.
Senior Member
Joined: Apr 2022
Posts: 379
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W211 E63 AMG
if you are driving at a speed that drops the engine RPM's for the gear you are in lower than 2,000rpm, the TCU will downshift. the transmission also utilizes skip shifting. should not be downshifting for no reason other than that. if there was an issue with the transmission internally, you'd most likely receive a code for that. if you're seeing odd behavior with the paddle itself, it may be faulty. try swapping out for another known good part.
MBWorld Fanatic!
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2005 e55 AMG
I think you answered your own question. The down paddle is getting stuck...why not replace it since they are cheap and easy to do.
The computer could be getting multiple up/down signals due to it being faulty.
The computer could be getting multiple up/down signals due to it being faulty.
Last edited by SICAMG; Jul 18, 2023 at 04:53 PM.
