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[steveyg_uk]

Morning,

Couple of questions if I may.

I'm Steve from Cambridgeshire region - just purchased my first 'SMART' car - forfour Passion.

1 - Reg flashing light on dash below the alarm OFF button whilst driving - is this normal?
2 - Am I correct in assuming these cars have 6 gears (mine is an auto box).
3 - Lag with AUTO box - does this drive (excuse the pun) anyone nuts?  Is there a software update that resolves the issue; or is more mechanial?

Many thanks.

Steve.

[Unknown]

Morning,

Couple of questions if I may.

I'm Steve from Cambridgeshire region - just purchased my first 'SMART' car - forfour Passion.

1 - Reg flashing light on dash below the alarm OFF button whilst driving - is this normal?
2 - Am I correct in assuming these cars have 6 gears (mine is an auto box).
3 - Lag with AUTO box - does this drive (excuse the pun) anyone nuts?  Is there a software update that resolves the issue; or is more mechanial?

Many thanks.

Steve.

Hello.

1. No, that appears to be a fault. The light should be off whilst driving.
2. AMTs have 5 gears with overdrive to produce 6 gears. I think petrol and diesel gearboxes slightly.
3. The auto-mode has lag and is annoying but you can lift off the throttle to ease the shift or drive in manual-mode for a lot smoother and more efficient drive.

Hope that is of help. As for software updates, you can enquire at your next service - Mercedes will charge a fee to hook up to a machine outside of a service.

[CrazyG]

I tend to disagree with "the AMT is 5 speeds with a overdrive 6th" as
I have compared the rpm/speeds in 5th on a manual verses the AMT
and they are different....with the AMT 5th revving more to acheive
the same speed.  However, I haven't yet managed to get hold of
a table of the gear ratios, so I'll not say I am 100 correct.

As to 'slow' gearchange.....it is no slower than a 'normal' manual
gearchange...it just appears to be slower. However, it definitely
will not be a s fast as a manual change if you are 'pushing on' a bit.

[basilbrush]

There is no overdrive on the Forfour AMT. Overdrive means the output speed of a gearbox is higher than the input speed. It's no good comparing the ratios of individual gears between the manual and auto boxes because they have different final drive ratios. The six speed box has a different spread of ratios which increases the fuel economy because you're more likely to be in the optimum rev and gear range.
I think when you're in auto mode the gearbox will seem laggy because the car is doing calculations of when to change based on road speed, revs, engine load etc. When you change gear in manual mode you just get the instant change which will probably be faster than any change you could do yourself with a normal gearbox.
The pdf below lists all the gear ratios for manual and automatic Forfours.
http://www.daimler.com/Projects/c2c/channel/documents/1138812_947227technische_daten_forfour_englisch.pdf

[Unknown]

I tend to disagree with "the AMT is 5 speeds with a overdrive 6th" as
I have compared the rpm/speeds in 5th on a manual verses the AMT
and they are different....with the AMT 5th revving more to acheive
the same speed.  However, I haven't yet managed to get hold of
a table of the gear ratios, so I'll not say I am 100 correct.

As to 'slow' gearchange.....it is no slower than a 'normal' manual
gearchange...it just appears to be slower. However, it definitely
will not be a s fast as a manual change if you are 'pushing on' a bit.

I honestly can't remember where the overdrive came from, its been that long since I first asked/researched about the 'box. It could be because the petrol AMT uses the same manual gearbox which has 5 gears so slapping an overdrive on would be a cost effective way to increase ratios. The original fortwo has a 3 speed with 3 over drives.

When I first had my forfour serviced they did the software update, and it felt completely different afterwards - the car could pull like a train in sixth without the revs hardly rising.

Okay I think I might be on to something, I searched for the Allshift variant (Mitsis name for the AMT) and found this thesis on the gearbox... http://www.mate.tue.nl/mate/pdfs/6215.pdf

The diagram shows a 6 cog setup with twin drums to smooth the shifts and no overdrive.

[lil.smartie]

450 is 3 speed twin diff.

[Problemchild]

the alarm light shouldn't flash - is the remote fob working ok?

what do the indicators do when you lock/unlock

JJ