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'06 SL55
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Discussion Starter · #1 ·
Interesting issue with my roof today. 05 sl55. I got in the car and wanted to close the roof since it’s super muggy today. I closed the roof and all was normal until the very last part of the sequence where the door windows close. The roof is closed all the way, trunk is closed all the way , the 1/4 windows closed all the way but the motor sound doesn’t stop unless I release the button. Tried multiple times opening and closing but won’t ever say roof closed on the dash. Thoughts?
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'03 SL500's Tanzanite Blue, Aegean Blue, Mars Red, Alabaster White '11 S550 Flint Gray
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It could be the frame lock switches or the front lock switches, but I think it is more likely that one of the latches is not fully closing. You can manually lock all three with the allen wrench that should be in your toolkit. Front latches are locked through the headliner. Remove the small plug by the rearview mirror. Frame locks are accessed by removing plugs by the trunk hinges on each side of the trunk. Make sure that all are latched and then check the roof status. If you have one not fully locked, chances are that cylinder is bypassing internally and not producing sufficient force to close the lock.
 

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Discussion Starter · #6 ·
It could be the frame lock switches or the front lock switches, but I think it is more likely that one of the latches is not fully closing. You can manually lock all three with the allen wrench that should be in your toolkit. Front latches are locked through the headliner. Remove the small plug by the rearview mirror. Frame locks are accessed by removing plugs by the trunk hinges on each side of the trunk. Make sure that all are latched and then check the roof status. If you have one not fully locked, chances are that cylinder is bypassing internally and not producing sufficient force to close the lock.
The awesome troubleshooting resource @rudeney provided points me in one of two directions -

Microswitch S69/2 and S69/3 OR Microswitch S118/1 and S118/2 - Both describe the same symptoms for the "open condition ( vs shorted/sticking) - Top Operates fully but pump continues to run and windows never fully close 1/4 gap remains.

Going to plug in my diagnostics and see if I get an error code for any of these as my next step.
 

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'03 SL500's Tanzanite Blue, Aegean Blue, Mars Red, Alabaster White '11 S550 Flint Gray
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Check position of those switches via diagnostic. If one is not recognized, try manually latching and check again. Even though two switches are listed for each, they are wired in series so both have to be closed for the latched position to be recognized. For the front latch, this is one cylinder that closes both latches, but the frame locks are independent cylinders. The switches are way more reliable than the cylinders, so keep that in mind.
 

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'06 SL55
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Discussion Starter · #9 ·
@MikeJ65 - I checked w an Alan key. The roof is definitely locked snug in the front. Unfortunately the scanner I have doesn’t seem to have the section for the top and doesn’t show and codes. So, in the process, the roof is closed all the way so I think I’m back to one of the two sets of sensors. Either it doesn’t know that the trunk is secured or it doesn’t know the roof frame is secured
 

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Also check both of the frame locks in the trunk. There is a plastic plug in the trunk lining covering each screw. They are on the sides towards the front of the trunk, right where your hinges are. From memory, I think the left one locks CW, and the right CCW, but it should be obvious when you turn them. If you go the wrong way, the front of the trunk lid will raise slightly.

You can also check switch status at the roof module. I think that the diagnostic guide tells you which pin they go to. Switched are recognized when they are grounded. I'm still betting on a bad lock cylinder vs. a bad switch.
 

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Discussion Starter · #11 ·
It could be the frame lock switches or the front lock switches, but I think it is more likely that one of the latches is not fully closing. You can manually lock all three with the allen wrench that should be in your toolkit. Front latches are locked through the headliner. Remove the small plug by the rearview mirror. Frame locks are accessed by removing plugs by the trunk hinges on each side of the trunk. Make sure that all are latched and then check the roof status. If you have one not fully locked, chances are that cylinder is bypassing internally and not producing sufficient force to close the lock.
I checked the frame lock in the front and they were fully closed but didn't know about the trunk. Gonna try this next
 

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Discussion Starter · #12 ·
Also check both of the frame locks in the trunk. There is a plastic plug in the trunk lining covering each screw. They are on the sides towards the front of the trunk, right where your hinges are. From memory, I think the left one locks CW, and the right CCW, but it should be obvious when you turn them. If you go the wrong way, the front of the trunk lid will raise slightly.

You can also check switch status at the roof module. I think that the diagnostic guide tells you which pin they go to. Switched are recognized when they are grounded. I'm still betting on a bad lock cylinder vs. a bad switch.
@MikeJ65 - I cannot get the trunk open. I am assuming that because it's mid-close there is some kind of lockout to prevent accidental damage? I use the manual key and nothing... Any suggestions?
 

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Discussion Starter · #14 ·
You have to turn the key to the left and then pull the handle.
Could I be that dumb??? LOL. Thanks I think I just turned the key. Don't exactly use a key in the trunk often in an MB.

Thanks for the quick reply
 

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Discussion Starter · #15 ·
@MikeJ65 - I guess this is the end my my abilities. My scanner has an MB module but doesn't see any codes. All 4 latches are definitely latched. Opens and closes but just won't complete that last step. I rarely drive it with the top up so I'm not in a huge hurry to get it fixed. I'm gonna drive by for a scan w my buddy from the AMG club, he's a Mercedes tech but he's 90 min away so I'll time it with a nice day and customer meeting...
 

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At least it opens and closes. Might need to check the wiring from the front latches. It has to move with the roof, so more potential for problems with that. Rear frame locks are fixed and wiring doesn't have to flex. Scan will at least tell you which set is the problem.
 

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Discussion Starter · #17 ·
At least it opens and closes. Might need to check the wiring from the front latches. It has to move with the roof, so more potential for problems with that. Rear frame locks are fixed and wiring doesn't have to flex. Scan will at least tell you which set is the problem.
Thanks. So co-incidental that I just washed it the day before.
 

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I had this problem. This can be caused by low oil level in the pumps reservoir. I had a leaky cylinder once or twice. I had to push the top manually down against the windshield frame and meanwhile my son operating the control switch.
 
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