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SLK320
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I got my 55 one week ago and found that the 7sp auto won't shift automatically if I am in C or S and have used the shifting buttons. I thought that it was truly manual only in M mode. If I start in C or S and don't use the buttons it's fine but as soon as I shift with the buttons once it is completely manual and won't shift automatically. This doesn't seem right to me. I also have the distorting tweeter problem with the HK system but otherwise the car is amazing! I can't wait to hit 1K.
Brad
 

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SLK350 (apr 15)
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I'm not sure if it's the same on the AMG as the 350, but the 350 works this way: once you go into manual shifting, it stays there until you explicitly take it out.

I don't have the buttons, so don't know if this works with the buttons or not, but if I press the shifter all the way to the right and then hold it, it'll run up the gears and then go back to indicating D in the gear setting, and it's back in auto mode.

My guess is that the AMG works similarly. You could, of course, RTFM to see if there's anything there ...

Good luck!
 

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SLK 55 AMG
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This is by design. That is the correct way for the gearing to work, and it shouldn't feel 'bizarre' once you understand why it is like that.

When driving, you can put the car into M mode, and immediately start on the gear that the car was riding on (for example, it'll show 7 if you're driving at highway speeds).

If however, you are in S or C mode, still driving on the highway, and you're feeling lazy, a quick tap on the leftside button will bring up M mode, but it'll display 6 (because you forced it to lower a gear).

You can bring the car back up to S or C mode by holding down the right hand button and keeping it pressed down for a few seconds. This will cause the autobox to cycle through the gears until it reaches 7th gear, and then turns back to full automatic.

The reason why you can go to manual mode even when in S or C, is just like in almost every other auto car. If you want, yu can still control the gears, and this could be a good thing if you NEED to use a certain gear quickly, without having to fumble for the SCM button.

Does this make it clearer? Remember, hold down the gear shift to the right, or hold down the right side gear selector button for a few seconds, and the car will go back to auto mode. This way, you can just about forget ever having to put your car into M mode, ever again. Just set your ride on C or S (which ever you prefer to drive in) and for those periods of 'play', tap the gear selector buttons and ride away [:D]

Anyway, what this does bring me to wonder, is the following:

We know that in S mode, the car is more responsive then in C. But if you bring it to manual mode by pressing the left gear selector button, is there a difference when doing this when in C mode, as opposed to in S mode? Will the engine be a bit more responsive when using 'manual' S mode, or will it be exactly the same as if you were driving in 'manual' C mode? Is there anything else that changes when going to S mode over C mode (I know in some cars, going to the equivalent Sporty mode from a Comfort mode, will cause the springs to stiffen, engine response to increase, etc...).
 

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2005 SLK55 AMG
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Shinigami, one thing I thought I read somewhere about the difference between M mode and C or S mode on SLK55, is that in C or S, even when using the buttons and going to the "manual" type mode (still with selector in C or S), that the computer will not let the engine redline. Where as in full M mode, I believe you can (and whatever I read, cautioned you).

Found it, pg 164, 165. It actually says you can damage your engine (SLK55 M mode only) if you allow engine to overrev (above redline), and that it is not covered by warranty (and you can bet the little computer watching you will record the event for MB techs to see!).

For C or S mode (including SLK350) computer will cut the fuel feed before allowing overrev.
 

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Interesting.

But is there any mention of the differences between C and S mode, apart from C keeping a gear for a longer time for smoother driving?
 

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SLK350 AMG Sport
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bloflin - 4/18/2005 10:11 AM

For C or S mode (including SLK350) computer will cut the fuel feed before allowing overrev.
In C or S mode it will also shift at readline even if you are in manual mode.
 

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My dealer told me on the test drive that C is 'cold weather mode' and S is 'standard mode'

If it's anything like the transmission in my Lexus, that means that it'll dampen out throttle response slightly, try and start in 2nd or even 3rd gear (on the 7 speed) and generally progress more smoothly to reduce loss of traction.
 

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2005 SLK350 2011 GLK3504X 2006 ML350(selling when GLK arrives)
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C is for "Comfort" mode; might be worth reading that section of the manual...[;)]
 

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alistairg - 4/18/2005 10:32 AM

My dealer told me on the test drive that C is 'cold weather mode' and S is 'standard mode'

If it's anything like the transmission in my Lexus, that means that it'll dampen out throttle response slightly, try and start in 2nd or even 3rd gear (on the 7 speed) and generally progress more smoothly to reduce loss of traction.
Interesting, my dealer told me that "C" was cold weather and "S" was summer. He was so wrong as Motzkoman points out "C" is comfort and "S" is sport or standard.

You wonder how the MB salesman can sell anything if they don't keep up with the mods.
 

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SLK350, BMW K1200LT
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malibuite - 4/19/2005 9:57 PM

alistairg - 4/18/2005 10:32 AM

My dealer told me on the test drive that C is 'cold weather mode' and S is 'standard mode'

If it's anything like the transmission in my Lexus, that means that it'll dampen out throttle response slightly, try and start in 2nd or even 3rd gear (on the 7 speed) and generally progress more smoothly to reduce loss of traction.
Interesting, my dealer told me that "C" was cold weather and "S" was summer. He was so wrong as Motzkoman points out "C" is comfort and "S" is sport or standard.

You wonder how the MB salesman can sell anything if they don't keep up with the mods.
Mal - did you buy your car, or was it sold to you - I've never been 'sold' a car in my life - I decide what I want to buy, and then go to a local stealer, who tells me 'what a wonderful choice you've made sir, etc., etc. but would you like this, that or the other', which I'd never go for, and then get a big commission from their bosses for clinching a 'steal' - it annoys me, but what keeps me happy is that I've got one, and they (the salesperson) hasn't -they're still working for a living
 

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Shinigami - 4/18/2005 10:45 AM

Interesting.

But is there any mention of the differences between C and S mode, apart from C keeping a gear for a longer time for smoother driving?
No. A number of pages in the manual on this. But basically C and S (Comfort and Sport) is just different shift points. Shifts earlier in C mode. Also in C mode starts in 2nd gear instead of 1st (unless you punch it to the floor).
 

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Well, I know my car will hit the redline in S mode and I don't understand why. You would think the computers could handle this correctly.
 

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Discussion Starter #13
Shinigami,
Thanks for the information. I guess this makes sense and I can certainly roll with it. It is quite a relief that there is not a problem with my tranny....Brad
 
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