SL/R230: SL500 R230 Vario Roof problems
Top works then stops
I have a 2003 SL500 that had leaking cylinders. I repaired said cylinders but now it operates fine except when coming from fully locked it raises the trunk then it seems to be trying to lock the front top lock instead of unlocking. I can then shut off the car and then after about 30 seconds it releases the front lock. I can then complete operation to open fully then back to fully closed. I have been racking my brain on this I hope someone can help me with this as I can deal with this but I would like to sell this car in proper working order.The only thing I can think of it being is the control module or the valves on the pump.
MBWorld Fanatic!


Joined: Aug 2020
Posts: 1,333
Likes: 365
From: Gretna, NE
'03 SL55 Black, '03 SL500's Aegean, Mars Red, Tazanite, Alabaster, '11 S550 Flint Gray
Since you have had cylinders off for repair, the first thing I would check is to make absolutely sure that every line is connected properly. Also verify that you have adequate fluid in the pump and that the pump bypass is tightly closed. I don't think you have a module or valve issue because the valve (y5) that controls the front latch cylinder is the same valve that controls the frame locks and the frame lift. Since your tubular frame is unlocking and lifting, the front latch should also be controlling correctly.
When you start to open, the main cylinders will push the roof tight against the windshield frame. This is normal so don't confuse it with the latch trying to close instead of open. With the roof fully closed, I would manually unlatch the front lock with the allen wrench. Then try to open the roof and see if you get a normal cycle. If it works properly, you have at least isolated the problem to the front latch not opening and can work from there. One possibility is that you are getting bypass on the frame lock cylinders and not building enough pressure to release the latch.
Did you have cylinders rebuilt or replace them with used? Also, which cylinder did you rebuild/replace.
When you start to open, the main cylinders will push the roof tight against the windshield frame. This is normal so don't confuse it with the latch trying to close instead of open. With the roof fully closed, I would manually unlatch the front lock with the allen wrench. Then try to open the roof and see if you get a normal cycle. If it works properly, you have at least isolated the problem to the front latch not opening and can work from there. One possibility is that you are getting bypass on the frame lock cylinders and not building enough pressure to release the latch.
Did you have cylinders rebuilt or replace them with used? Also, which cylinder did you rebuild/replace.
Since you have had cylinders off for repair, the first thing I would check is to make absolutely sure that every line is connected properly. Also verify that you have adequate fluid in the pump and that the pump bypass is tightly closed. I don't think you have a module or valve issue because the valve (y5) that controls the front latch cylinder is the same valve that controls the frame locks and the frame lift. Since your tubular frame is unlocking and lifting, the front latch should also be controlling correctly.
When you start to open, the main cylinders will push the roof tight against the windshield frame. This is normal so don't confuse it with the latch trying to close instead of open. With the roof fully closed, I would manually unlatch the front lock with the allen wrench. Then try to open the roof and see if you get a normal cycle. If it works properly, you have at least isolated the problem to the front latch not opening and can work from there. One possibility is that you are getting bypass on the frame lock cylinders and not building enough pressure to release the latch.
Did you have cylinders rebuilt or replace them with used? Also, which cylinder did you rebuild/replace.
When you start to open, the main cylinders will push the roof tight against the windshield frame. This is normal so don't confuse it with the latch trying to close instead of open. With the roof fully closed, I would manually unlatch the front lock with the allen wrench. Then try to open the roof and see if you get a normal cycle. If it works properly, you have at least isolated the problem to the front latch not opening and can work from there. One possibility is that you are getting bypass on the frame lock cylinders and not building enough pressure to release the latch.
Did you have cylinders rebuilt or replace them with used? Also, which cylinder did you rebuild/replace.
MBWorld Fanatic!


Joined: Aug 2020
Posts: 1,333
Likes: 365
From: Gretna, NE
'03 SL55 Black, '03 SL500's Aegean, Mars Red, Tazanite, Alabaster, '11 S550 Flint Gray
Do you get any warning messages like the roof not being locked? I can see a possibility where the roof tries to open with the front latch still locked, assuming that the switches are incorrectly showing it unlatched. The second attempt might work because you have the trunk frame open and frame unlocked, so all fluid in valve 5 is feeding the front lock and it unlocks immediately.
I would put the allen wrench in the front latch and see what it is doing when you try to open the roof. Can you assist it enough to unlock it? Did you have the front cylinder professionally rebuilt or just do an O-ring fix? You might be getting some bypass around the piston seal, especially if it wasn't replaced. Even if it was a professional rebuild, the seal could have been damaged unknowingly when it was reassembled. Like I said earlier, one valve controls the frame locks, trunk lift, and front latch, so I don't see how it could be a valve or control issue for the lock cylinder if the trunk is lifting and frame locks releasing.
Also, when you first start to lower the roof, you should see and hear it trying to push forward at the windshield. This is to relieve pressure on the front latch so that it can unlock. Since the roof main cylinders are opening and closing the roof, they should also be able to push if forward at this stage, but it is something to check.
Do any of the roof steps seem slower than they should be?
I would put the allen wrench in the front latch and see what it is doing when you try to open the roof. Can you assist it enough to unlock it? Did you have the front cylinder professionally rebuilt or just do an O-ring fix? You might be getting some bypass around the piston seal, especially if it wasn't replaced. Even if it was a professional rebuild, the seal could have been damaged unknowingly when it was reassembled. Like I said earlier, one valve controls the frame locks, trunk lift, and front latch, so I don't see how it could be a valve or control issue for the lock cylinder if the trunk is lifting and frame locks releasing.
Also, when you first start to lower the roof, you should see and hear it trying to push forward at the windshield. This is to relieve pressure on the front latch so that it can unlock. Since the roof main cylinders are opening and closing the roof, they should also be able to push if forward at this stage, but it is something to check.
Do any of the roof steps seem slower than they should be?



