I have only had my 2003 R170 SLK since Feb but love it - it's a fun drive, looks great & love the convertible features - a nice summer really makes for enjoyable driving with the roof down.
However, like with all new toys, I usually look for ways of improving it so I bought & installed the Smarttop module which greatly improved my enjoyment of the convertible. I'm sure you all know the Smarttop features & the operational flexibility it gives.
One feature that is missing from the R170 Smarttop (which is included on the R171/172 Smarttop) is control of the rear quarter windows - in the R170 they are always in the down position when the roof is open. I wondered what additional wind protection would be achieved by having these windows up along with the front windows
Anyway, I had to adjust one of my rear quarter windows as it wasn't aligning itself properly with the front window rubber seal. While doing this I decided to experiment with how the car would look & feel with all windows up & the roof down (I just disconnected the power to these rear windows to stop them going down). It looked great but alignment of windows is crucial to the look - with good alignment it then forms a nice glass curve from top of front windscreen to where it goes into the bodywork behind the seats. Much more aesthetically pleasing than the cut-off look with just the front window raised.
It also does improve the wind chill factor & noise although I didn't spend too long driving around with it like this as when I went out for a drive, typical Irish weather reared it's head & it looked like imminent rain. I didn't want to look like a wally with the rain pouring into my open car so I drove home.
Why couldn't I have just closed the roof with the rear quarter windows up? I had tried it before I went out for a drive & noticed that 2 rear shelf quarter flaps need to pivot for the roof closing & they don't do this with the windows up (I slightly strained one when closing the roof before I noticed this).
So I believe if the rear window raising/lowering is linked to the electrical control of the front windows we probably will have what we need - both windows up or both down (I don't see the need for individual control of front/rear windows)? That means when the front window goes down automatically for the roof opening, the rear window will follow suit & ditto for when the roof is closing.
Now the only final issue is that the rear window doesn't have an end-stop electrical control like the front window has i.e. power to the motor is disconnected to the front window when it reaches it's end travel. This prevents the motor from burning out or the window mechanism from being strained trying to move against it's physical stops.
The rear windows don't have these electrical disconnects at the stops, I believe. Their operation is timed by the control unit - it raises the window for 3 secs (with a little 0.1 sec spurt when the roof is closed) & I presume lowers it for this length of time also. So the motor runs for just 3 secs in either direction? I have sourced a timed programmable relay which can be set to run for 3 secs (or any reasonable time) & then disconnect power which, if powered from the front window operation, will do just what is needed.
This would work perfectly for all automatic operations of the windows. There's only one glitch in all of this - if you manually raise or lower the window half way (>3sec power), the rear window will be raised or lowered fully. No problem with this. But if you then decide to further raise/lower the front window the connected rear window relay will do another 3 sec power sequence & try to run the motor against it stops for 3 secs.
I haven't figured out an easy way to handle this yet - it may be simply a case of supplying reduced current to the motor so that it isn't under much strain when trying to operate when physically stopped but has enough current to raise & lower the window. Maybe someone here can answer this?
One answer is to go with a fully manual control on the rear windows but this does give another problem - what if you forget to lower the rear windows & you close the roof? - the rear parcel shelf flap will be mangled & probably other damage done?
So, I would be interested in teasing this out to find a 100% solution. It's probably a 99% solution, at the moment & easy to implement - no switches, automatically following the front windows behaviour, no changes to the cars interior - just needs wiring into the loom - I haven't decided where is the best place to do this yet? It should also be completely reversible.
However, like with all new toys, I usually look for ways of improving it so I bought & installed the Smarttop module which greatly improved my enjoyment of the convertible. I'm sure you all know the Smarttop features & the operational flexibility it gives.
One feature that is missing from the R170 Smarttop (which is included on the R171/172 Smarttop) is control of the rear quarter windows - in the R170 they are always in the down position when the roof is open. I wondered what additional wind protection would be achieved by having these windows up along with the front windows
Anyway, I had to adjust one of my rear quarter windows as it wasn't aligning itself properly with the front window rubber seal. While doing this I decided to experiment with how the car would look & feel with all windows up & the roof down (I just disconnected the power to these rear windows to stop them going down). It looked great but alignment of windows is crucial to the look - with good alignment it then forms a nice glass curve from top of front windscreen to where it goes into the bodywork behind the seats. Much more aesthetically pleasing than the cut-off look with just the front window raised.
It also does improve the wind chill factor & noise although I didn't spend too long driving around with it like this as when I went out for a drive, typical Irish weather reared it's head & it looked like imminent rain. I didn't want to look like a wally with the rain pouring into my open car so I drove home.
Why couldn't I have just closed the roof with the rear quarter windows up? I had tried it before I went out for a drive & noticed that 2 rear shelf quarter flaps need to pivot for the roof closing & they don't do this with the windows up (I slightly strained one when closing the roof before I noticed this).
So I believe if the rear window raising/lowering is linked to the electrical control of the front windows we probably will have what we need - both windows up or both down (I don't see the need for individual control of front/rear windows)? That means when the front window goes down automatically for the roof opening, the rear window will follow suit & ditto for when the roof is closing.
Now the only final issue is that the rear window doesn't have an end-stop electrical control like the front window has i.e. power to the motor is disconnected to the front window when it reaches it's end travel. This prevents the motor from burning out or the window mechanism from being strained trying to move against it's physical stops.
The rear windows don't have these electrical disconnects at the stops, I believe. Their operation is timed by the control unit - it raises the window for 3 secs (with a little 0.1 sec spurt when the roof is closed) & I presume lowers it for this length of time also. So the motor runs for just 3 secs in either direction? I have sourced a timed programmable relay which can be set to run for 3 secs (or any reasonable time) & then disconnect power which, if powered from the front window operation, will do just what is needed.
This would work perfectly for all automatic operations of the windows. There's only one glitch in all of this - if you manually raise or lower the window half way (>3sec power), the rear window will be raised or lowered fully. No problem with this. But if you then decide to further raise/lower the front window the connected rear window relay will do another 3 sec power sequence & try to run the motor against it stops for 3 secs.
I haven't figured out an easy way to handle this yet - it may be simply a case of supplying reduced current to the motor so that it isn't under much strain when trying to operate when physically stopped but has enough current to raise & lower the window. Maybe someone here can answer this?
One answer is to go with a fully manual control on the rear windows but this does give another problem - what if you forget to lower the rear windows & you close the roof? - the rear parcel shelf flap will be mangled & probably other damage done?
So, I would be interested in teasing this out to find a 100% solution. It's probably a 99% solution, at the moment & easy to implement - no switches, automatically following the front windows behaviour, no changes to the cars interior - just needs wiring into the loom - I haven't decided where is the best place to do this yet? It should also be completely reversible.
