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i have an 03 sl500. bought the car with the roll bar stuck in the up position. I read many posts and tried everything I can think of and what was suggested to do. Nothing works. The previous owner must have went air born with the car because the bottom of the front bumper is all torn up. Any other suggestions on what could be wrong? Does anyone know of a good mechanic in the New Jersey, Delaware area? Any help would be deeply appreciated.
2005 R 230 SL350 (M112 3.7). Sold the 1966 W113 230SL recently
Did you try holding the switch 'up' untill you hear a mechanism clicking in? Does the pump run when you do?
Perhaps your bar is up after an incident induced trigger (is that English?). Your bar needs to be all the way up before it can be lowered. If that doesn't work you'll have to dismantle interior panels and release the mechanism mechanically. Careful, read other posts about this.
Presuming the hydraulics and controls are all working.
Hi Frederick thanks for replying. Yes I tried holding the lift button. Tried many times did not work. The pump makes noise when i hold the button to make the bar go down. I even replaced the entire lift mechanism on the passenger side. its still stuck up.I see the spring move when i hit the button but thats all it does. But what i did notice is that the spring on the drivers side did not move to release that side at all. I dont think its getting any fluid to release the spring. I have an autel scanner it said the pump is in good shape. Any more suggestions?
1) Your scanner cannot verify operation of the pump, there is no pressure transducer.
2) Since you replaced the cylinder, was there adequate fluid in the pump and does the cylinder move when you try to raise and lower the bar? During emergency operation, the cylinder detaches from the cylinder and the spring on the left side deploys the bar. To lower, the cylinder needs to first be raised and reengaged.
Yes i replaced the entire unit. And yes the pump has plenty of fluid in it. In fact i put more in it after i replace the unit plenty of fluid came out after i cut the lines. Yes the cylinder is engaged. When i push the button i see the spring move but thats all that happens. The spring on the driver side doesnt move at all. Maybe its not getting fluid to the driver side to move the spring. Also i checked the fuse it was good. Maybe a relay is bad? I dont know.
So the actual cylinder on the right side is fully extended and does not retract? What happens when you try to open the roof? Do you see the roof pushing forward, tight against the windshield?
It is possible that your pawls are not releasing, but I'm not quite convinced. You can manually release them and lower the bar manually. That probably won't solve the problem, but it will help you diagnose.
When i try to open the roof the trunk opens up and thats it. I hear a click like the top want to move but it wont because the bar is up. And i tried to put it down manually. That didnt work. My son was on the left while i was on the right side. It was like the cylinder wouldnt release. It was like for some reason the pressure stayed pushing the cylinder up. I went to the pump to relase the pressure on the pump thinking that would help but nothing. Im thinking maybe a solenoid on the pump is bad or maybe the pump it self is bad.
Lifting the trunk requires some decent pressure, so I think it is likely that your pump is OK. One thing I have learned is to never underestimate how badly people can screw up a Mercedes. Since it has not worked since you have owned the car, don't assume that anything is assembled correctly. I would start by checking the pawl and roll bar lines to make sure that they connect at the proper ports on the pump. Pawl lines are 102 and 103, rod side of the roll bar cylinder is 100, piston side is 60. Since it sounds like you spliced the lines for the roll bar cylinder, make sure that they are matched correctly. If that all checks, I think I would remove the right side and see if it works when disconnected from the roll bar. If not, manually release the right side pawl and try again.
The two pawls are on the same valve and the rod side of the roll bar cylinder is pressurized whenever the pump runs. It is also the only line that holds pressure when the pump stops. The piston side of the cylinder should normally be open to drain, so you should be able to push it down when lowering the bar manually. It is possible that the valve is stuck 'on' and continuously pressurizing the piston side, forcing the bar up. You could remove line line 60 at the pump to test this. If that allows the roll bar to now be manually lowered, it would point to a valve problem (don't run the pump when you are trying this).
2005 R 230 SL350 (M112 3.7). Sold the 1966 W113 230SL recently
Knowing that Mike's knowledge is far superior to mine I would still like to stress that the pressure in the roll bar lines is high. Which is why WIS warns to take care when loosing them, as a brief but fierce spout can harm you, penetrating skin.
WIS often is like an over concerned mom with its warnings, but this one does sound plausible.
Ok when i replaced the unit i marked the lines so i wouldnt get them crossed. So that is good. Im gonna try to remove line 60 from the pump and try then. When i removed the old unit i had to destroy some of it because the cylinder would not compress so i could get it out. When i got it out i went to the left side and tried to push it down and it moved. So i know the bar itself is not jammed. Like you said that valve may be stuck in on position and thats why the line stays pressurized and i cant push it down. Im gonna try that tonight when i get home. Thanks for all your help. I will repost after i try it. Thanks.
Hi Frederick thanks for replying. Yes I tried holding the lift button. Tried many times did not work. The pump makes noise when i hold the button to make the bar go down. I even replaced the entire lift mechanism on the passenger side. its still stuck up.I see the spring move when i hit the button but thats all it does. But what i did notice is that the spring on the drivers side did not move to release that side at all. I dont think its getting any fluid to release the spring. I have an autel scanner it said the pump is in good shape. Any more suggestions?
Wondering why you replaced the entire unit on the passenger side to begin with? Was it leaking?
If you raise the roll bar with up button, both pawl cylinders should push in against the springs and relased the mechanical latching part (big black teeth rail). if one of the spring is not release, Roll bar just won't move at all. I suspect driver side pawl leakage(internal/external).
Keep this in mind if one wants to open the top and roll bar is in up position, system will lower the roll bar first, complete the top stow cycle and then raise the roll bar.
Also when you replaced the entire unit on the passenger side, those lower bolts may change the roll bar alignments.
When you lower the roll bar manually, did you and your son use screw driver up against the spring method?
I bought the car in this condition. I replaced it because i thought it was faulty. I said in my earlier posts that i tried everything that i read about in the forums and everything i found online and nothing worked. Thats why im here asking for some help. This is my first time working on a convertible car so i dont know much about it. We used the method with the screw driver that i saw the mercedes technician use on you tube.
Last edited by Mking4469; May 4, 2022 at 07:34 PM.
Hey MikeJ65 you are so right when you said people mess up a Mercedes and don't assemble things right. I went to disconnect the #60 hose and guess what I find out? Someone had the pump apart before and put half of the hoses in the wrong ports. My 60 is in the 100 port. 102 is in the 22 port and so on. So I'm thinking that this is the problem. I will correct this on the weekend when I have more time. After i correct it i will make a post of what my outcome is. Thanks for all the help everyone.
If the pump does not have internal problems (internal check valve leakage, pressure relief valve..debris blockage..etc), both of the pawl lock cylinders should move as soon as you push the roll bar buttons.
When you hear the pump running, doesn't mean it is building up enough output pressure. Without pressure, nothing will work. Pawl locks/springs movement is the first good sign.
I would try holding the roll bar up button for few seconds at a time, do it few times. You don't want to overheat the pump. Meanwhile check for pump fluid level, other leakage. if there's leak, it won't build up enough pressure.
Another test is, remove line 60 from the valve block. While you push and holding the up button, fluid should come out. Make sure you put some towel around it.
I've had the same thing happen on PSE pumps, lines just connected at random and those aren't marked. Hopefully whoever worked on the pump didn't do much other work on the car.
2005 R 230 SL350 (M112 3.7). Sold the 1966 W113 230SL recently
Just in case you didn't notice: the original hydrau lines are all marked with their number. Numbers are also embossed on the retaining plate of the pump.
Yes i saw that. Thats how i knew the lines were in the wrong ports. Thats why when i hit the raise and lower buttons the right spring would move and the left side dont. Other than this roll bar issue the car seems to be in decent shape for an 03. Thanks for your help. I will post results after i correct the issue.
"UPDATE" I want to thank everyone who gave me suggestions and help with my roll bar issue. It is now fixed and working as it should. I was able to see my roof go down for the first time. The problem was previous owner let someone work on the pump and they put a lot of the lines in the wrong ports. So i took all the lines out and re installed them all to the correct ports. I added a little fluid crossed my fingers and pushed the button. And magic happened, down went the roll bar. So i really appreciate all the help from everyone. I will be getting tags and registration this week to see what it feels like on the open road.
2005 R 230 SL350 (M112 3.7). Sold the 1966 W113 230SL recently
Good on you. Now, of course, check your fluid level each few cycles as air bubbles will escape to the reservoir. After that, level checks will rule out cilinder leaks.
Yes i will do that. Thanks for the advice. One other thing i have to do is mark each line again because the painted on numbers are fading really bad. A couple of them was really hard to make out. So i bought some of those stick on numbers that electrians use to mark their wires to number my lines again. Next thing to fix is the soft close on the trunk. When i hit the trunk release you hear nothing but air.
2005 R 230 SL350 (M112 3.7). Sold the 1966 W113 230SL recently
When i hit the trunk release you hear nothing but air.
Don't know what that means but there's a sticky about fixing a leaking soft close. Until you get at it, try not to slam the trunk lid too vigorously as that may crack your 3rd brake light, causing a potential leak and you want to keep the trunk bone dry. Enough hydrophobic stuff in there.
Nice work. I wonder what percentage of Mercedes dealers would have gotten that repair right on the first attempt. I think around 60% would have replaced the right cylinder assembly, 30% would have put a new pump in, and 10% would have just billed diagnostic time and labor time to rearrange the lines.
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