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Hello all, just got myself a 1996 sl500. Needs a ton of work been sitting outside not started for about 5 years, shame.
(The last owner did put a charge on the battery before he bright it over and i don't think he disconnected the neg battery lead)
When i got the car it had the hard top on it. The car would not release to hard top electrically. Did fine a nice you tube video on how to release it manually so i got that off.
Trying to get the roll bar and the soft top two come up. Both are down as of right now. After resyncing the windows i try a raise the soft top. No movement at all. what happens when i push the button forward is both windows come down, the red light in the button is solid till the window gets about 2/3 way down then begins to flash.
I do hear what sounds like a latch opening and closing.
My first 1st question, should the hydraulic motor be running at this point? I don't think it is.
Mt second question, can someone point me to a good shop manual, i am going to need it lol
Thanks in advance
Yes, the pump should be running. If not, check fuses and the pump relay.
Also look down into the read latch holes and check the depth of the latch. They should both be the same. If not, one of the latches is still locked (I have had this happen when removing the hardtop). One of the symptoms of this is the sound of the latch trying to unlock.
One thing to try is to manually raise the soft top (Youtube) just to the point where the front bow contacts the windshield header. See if you can get it to cycle back down or even cycle forward.
Ok here is a update.
removed the neg lead from battery, left it off for about 4 hours. replaced then sync windows. tried top with no luck Ok hydraulic pump not coming on. check voyage at relay found that when the switch is pushed forward i get voltage at pin 87 (this is the supply to the motor i think) but no voltage to pins 86 or 85 (the pins that pull the relay in) What i think there is something not allowing the pump motor to come on. But what/were does this come from? IDK
LOL need a shop/electrical manual any recommendations?
The pump relay is driven by the top controller, N52. There are many error conditions that can cause the pump to shut stop to protect the system, many of which are related to microswitch state issues. Try what I said about manually raising the top - the worst that can happen is you will have to put in back down.
FYI, here is the pump portion of the top system schematic:
OOps Sorry my bad.
yep did what you suggested opened and raised the top by hand, then tried to operate it electricity tried to raise and lower the top at about 1/2 up, also just touching the windshield liner and completely latched in full up. still nothing. no movement.
so i do think the motor has to run, how do i go about figuring out why the motor is not running?
also downloaded a manual from manual4you it is no help does not cover any hydraulics
Bummer! I was hoping that moving the positions of the microswitches may clear enough issues that the pump would run. Have a friend activate the top switch while you feel the pump relay - does it click?
Nope, tried that lol also did voltage checks at relay base, the supply leg is the only place i get anything. nothing at the control legs. So either i got a Bad switch someplace or BAD ecm or a broken wire or something like that is what i am thinking. Got to figure a way to find all the switches so i can check them. thats next lol. also sent a email to BBA se how much it going to cost to get the EMC fixed
do you have anything showing all the switch locations?
20 years ago there was a song 'You've got a tiger by the tail'. Trying to diagnose your convertible top hydraulic system without a system diagram is all but impossible. There ARE several good posts in the R129 forum on removing the 12 (or 11) hydraulic cylinders that point out some of the switches. There are 12 (or 11) solenoid activated valves directing hydraulic fluid to/from the cylinders in the proper sequence to open and close the top assembly. All those micro-switches must work correctly to tell the top controller to go to the next step.
Question, been looking at getting a blink reader for my 96 sl500 to help fix the soft top and roll bar issue. but they all say up to year 95. The car does have a OBDII socket but that shows NO codes. The car does have the 38pin dig port (i think its 38 pin lol) will a blink reader work?
If you have one of these: https://www.tillmantools.com/product...RoC8SUQAvD_BwE you can still use a blink code reader to read the top codes, but these are pretty hard to find these days (I still have one) as they have long been superseded by modern, inexpensive code readers that have a 38 pin adapter. Instead of spending money on the breakout, I would recommend the Foxwell Tools NT530 with the Mercedes software and the 38 pin adapter (https://www.foxwelltool.com/wholesal...RoCgCsQAvD_BwE ). I have one it works works like a charm! Indeed, it works so well that I rarely breakout out my Star system.
Hay thanks for the info, but i am a little confused. I was looking at the PDF of the functions on the NT530 under (s)129 and don't see any thing that points to the soft top or the roll bar. So am i looking in the right spot?
I have periodically had the Soft Top control module rebuilt by BBA Reman... yes, they're back up an operating with a wiz technician they imported from Mexico, and they do stand by their warranty.
All hydraulics rebuilt by Top Hydraulics (the Phoenix heat just dries the seals out).
It was working until my wife was putting the top up, and it crapped-out midway up.
I checked the 40A fuse in slot #9, and it was okay.
I presumed it was the controller, so I sent it back to BBA Reman for repair... however it took a while because they were down because of the pandemic and short staffed.
I ordered another used controller from a Calif salvage yard-- and it didn't solve the problem-- the up/down button was still lit red, and no activation sounds from the pumps/ windows did not work either. Could also be a bad control module...
Just got the rebuilt controller back from BBA, popped it in, and still no joy!
Safe to conclude it's probably not the control module, and the 40A fuse is good. I am not a technician and cannot chase down any circuitry... other than swapping/replacing parts.
What's next to check? Relay? ....or would there be another fuse to check for the power windows? Klaus at Top Hydraulics said it's probably not the relay as they don't normally go bad...
I have no way of reading error codes.... is there anything semi-obvious I can check, or is it time to bring it in to a Mercedes maven?
08-25-2020, 02:39 PM
Ok hydraulic pump not coming on. check voyage at relay found that when the switch is pushed forward i get voltage at pin 87 (this is the supply to the motor i think) but no voltage to pins 86 or 85 (the pins that pull the relay in) What i think there is something not allowing the pump motor to come on. But what/were does this come from? IDK
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