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Discussion Starter #1
Hi,

did some serching on this forum and didn't find answer to the thing that got me confused.

I bought my mercedes couple of months ago and had to do many varius small fixes, including replacing old vario roof o-rings.
Now the roof works and goes up and down like it should. But i noticed that i can't put top up or down if the car was moving before. So again, if i put ignition in position 2 or just start the engine i can put top up or down as many times as i want, but if i go for i drive and then stop, engage hand brake and try to lower or raise the top nothing happens and light in the switch just blinks, i have to turn off the engine and then put the ignition to again position 2 or start the car to be able to raise or lower the top.
Is this normal behavior, in the manual it just says to stop the car and apply the handbrake, nothing on turning off engine and restarting? if this is not normal, what could be the problem? It's really anoying that i must be completley stationary to oparete the roof, restarting the car to do it it's just bit to much. I probably will instal auto roof module in the future, but i want to be sure that everything is ok before i do that so there won't be any unplesant surprises. R)
It's 1998 230 kompressor with manual gearbox.
 

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You shouldn't have to restart the engine to get the roof to work. I suspect it has something to do with the transmission. Do you have it in neutral? Do you have to have the clutch depressed? I'm sure there is some sort of safety interlock so you cant actuate the roof while in gear. I checked the manual but it isn't terribly helpful.
 

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Premium Member 2005 SLK55 AMG; 2005 SLK350
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This is not normal.

The roof module prevents roof movement when the car is in motion, but does not care whether the engine is running, what gear you are in. As long as the key is on and you are not moving the roof should operate.

Of course the luggage partition must be extended.

Usually when the light is blinking it means one of the switches is bad (or the wiring). I would start with a good (STAR or equivalent - not OBD) scan during the failure, or troubleshoot your switches with a automotive test probe.
 

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Premium Member 2004 SLK200K
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Are you 100% sure a previous owner didn't install a roof module already?

I once had a similar problem with a car with roof modules installed and it was due to the 50km/h module being faulty...
 

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Discussion Starter #5
You shouldn't have to restart the engine to get the roof to work. I suspect it has something to do with the transmission. Do you have it in neutral? Do you have to have the clutch depressed? I'm sure there is some sort of safety interlock so you cant actuate the roof while in gear. I checked the manual but it isn't terribly helpful.
If I recal i tryed with gear in neutral and then also with clutch depressed, nothing changed.
 

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Discussion Starter #6
the roof module is not instaled if i it' tipical smart top type of module, becouse i was checking k40 relay module for separete issue and didn't see any box in there, althou someone has been doing somthing inside that ecu box cuz all the wiring was a bit messed up, but nothing riped or not connected.

A also don't think that any regular switch isn't working, becouse after restart it operates normaly like it has to, no problem up or down. I just don't know what could be the problem when i start driving and then stop. Is there any switch for transmition or clutch that would disable vario roof in maual transmition, could they be faulty?
 

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Now, how does the car know it is moving? Either, it senses motion (some cars can do that) OR it senses speed (most cars can do that).

If your car is OK from standstill (no motion detected, either way) but thinks it may still be moving after actually traveling for a while - I would guess in the direction of a faulty motion sensor (used for functions connected to dynamic stability enhancement, ESP). Not all cars have it, however.

Do you have ESP and does it work? Is the speedometer working as it should? Are there any fault codes from any sensors? (with ESP, there is a inertia sensing relay (nowadays found in any cellphone) right in the middle of the car, close to the handbrake (IIRC).

(The roof isn't supposed to be activated at any speed, really. The forces on that big upright sail is tremendous, and it is eminently possible that the combination of a headwind of 20 knots, added to 50 km/h would result in a effective windspeed of 90 km/h... So, if going the roof module way, keep this in mind)
 

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Discussion Starter #8
I don't have equipment to read fault codes, but nothing seems to be wrong with abs sesors. Car is pre ESP model, but it has ASR and it works ok, i regulary put to much power down and it kiks in like it should and stop the wheels from spining, also i don't have any warning light on the dashbord that would indicate anything is wrong. I too suscpect somehow car doesn't know that it's not moving, but i didn't put too much atention to this problem until now because i was not shore if the roof should work like this and because is winter curently here in slovenia so i only put the roof down twice so far anside from testing it after o-rings replacment.
 

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Registered 1999 SLK230
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For what its worth, i use the KISS method when fault finding,
and the assumption that most things aren't as complicated as they may seem.

And im sure one of our learned friends on here will chime in, in due time with a logic
diagram for the roof (or similar)

But i would imagine that there would be an interlock somewhere in the
Gear train to make sure you are not moving.

for example, you are in neutral with the clutch out.

Anything else would be designing in additional complexity for no reason.

What ever that interlock is, it must be able to be over ridden for the smart tops
To work.

So if you are able to use the roof, before moving off, but once you have moved
You cant use the roof until the car has been restarted.

I would suggest the interlock switch (where ever it is ) is being effected
By vibration, and possible causing a fault which is cleared on restart.

Whish i could be more help

Cheers from downunder

P.s always happy to be proved wrong, and will follow
thread because i am interested to know the answer
 

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Super Moderator UK SLK 55 AMG 2007
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I can't remember if this was force of habit with our 230
or required.

I used to keep my foot on the brake.

I'm wondering if there is a sensor there.

as in, if your foot is on the brake, it isn't on the gas
therefore the car cannot be moving.

Not got a clear head on at present.
Check if the vac lines (probably yellow) on top of the pse
are correctly located and not kinked.

Also, check pse is not wet.
 

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Premium Member 2005 SLK55 AMG; 2005 SLK350
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I've only worked on pre-FL R170 with automatic transmissions - it is possible that the logic differs automatic transmission vs. manual transmission. I am not sure.

The roof module learns the car speed indirectly, via a signal from the ESP/BAS or ASR/SPS module. I believe, from this site, it's one of the front wheel sensors. If it fails, another warning light on the IC will come on.

The roof module learns the state of S69/12 (trunk lid rotary tumbler/trunk light switch) indirectly, via a signal from the PSE. Does your power lock/unlock seem to work OK?

The wiring for S69/12 is prone to breakage, check your wiring harness in the hinge area of the boot lid. These wires flex every time you open the boot lid and this causes the wires to break.

Really, there is no "logic diagram" that I've seen, and this is one of the more complex systems in the car. If you don't want to take it for a scan, and you don't want to test the switches, there's not much else you can do.
 

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Registered 1999 SLK230
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That makes sence - use the sensor that is already there, and no difference required between manual and auto

I love this site so much to learn

Cheers fron down under

Edit- just read that the top in an unmodified SLK does not need to be totaly stopped.

In the docment i read is that 1 or 2 kph and it should work.
Seems a pointless speed so supports a speed sensor, as stated above
 

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Discussion Starter #13
Power locking seams to work ok, nothing it locks and unlocks like it should and turn signals blink when i do it. I don't recal if i had my foot on the brake when i tryed lowering the roof so i might ry this nex time just to be shore. Anyway, now that i know that i don't have to restart my car I will try again to figure this out when i'll have some time and the weather will be a bit better. I'm sure this is just a minor thing and i'm just missing something obvious.
 

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Discussion Starter #14
Just a little update. I was playing with the rooof a while ago and to try to figure out what the problem was. The roof went up and down if i started the car and I didin't move, also it was ok if I moved gently few meters (going more than 5 km/h) and then stoped to lower the roof. But if I drove for even short distance and stoped, I couldn't move the roof again until i restarted the car so idk, looks like something is tripping the controller to think i'm still moving if I move more than lets say 10 seconds.

Anywhay, I got myself one tuch module with 50km/h module and remote control function. I installed module and went for a test drive like specified in instructions. Now, the roof works with no problem, i can lover or put the roof back up while driving or not moving, so I asume there was no hardware problem like a switch gone bad because of vibrations, just controller thinking the car is still moving while it was at rest.

Intresting thing this little glitch, hope that someone some day figures out what is the couse if they have the same problem.

BR
 
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