[Canex]

Hi all ,
1990 300 SL was working fine then flat battery. Replaced battery - sun came out - remove hardtop - night came - raise hood - problem!
The deck was trying to raise one side OK - other wouldn't move - then both raised OK. BUT hood wouldn't lift!
If I lift it manually it works fine - locks - even folds away as good as gold - but it won't lift after the deck has gone up.

I have read all the threads I can find and have tried all the suggestions:
read the fault codes - reads 1 - all OK
reset the codes
reset windows & roll bar (10 seconds at each setting)
uncoupled battery for 10 mins
No hydraulic leaks
Level of fluid is fine

everything works Ok apart from the 2 main hydraulic rams won't push the hood up!!!!
There must be something telling them not to work
PLEASE HELP !!
does anyone have the hydraulic/electric diagram for the hood so I know where to start looking for a faulty sensor/relay/bypass valve/ram ????
I am not sure it is to do with the battery being changed, the pump is running & there is movement from the hood when it is trying to lift and relays clicking - but if it is stopped when folding down it cannot raise again & will still fall with gravity even if the switch is being held on.
Please someone save me from certain insanity !!!!!!!

Chris

 

[Canex]

Does anyone know if the repair DVD can be bought in the UK? I have the WIS programme but find it almost impossible to run (I have it on 3 computers & it doesn't seem to work properly on any of them)
I am still looking for help to find which relay/pump etc powers the main two cylinders to raise the hood up. It has a number 70 on the hydraulic pipe from the cylinder but I can't see where that goes to?

cheers
Chris

 

[RedLiner]

Chris, I have looked on my Alldata CD's for your year and model R129.

There are plenty of electrical diagrams but they would take up pages of forum bandwidth to screen grab and post them up, likewise with the hydraulic info.

There is a topic on how to obtain the Alldata CD's just search for Alldata.
If you can point to a specific part of the circuit diagram I will try to find it and post it up. Looking at the hydraulic diagrams I could not see any reference to a pipe Nº.70.

I'm sure that when our soft top experts pick up your post they will comment, unfortunately sometimes these members are not always available to answer queries straight away.

 

[mhabie]

Just a helpful hint about Alldata. I don't know about the UK, but here on Long Island,NY, you can go into a library in the reference center and access their computer with Alldata on it for free. Free printing for 5 pages, and then 10¢ a copy.

 

[Canex]

Thanks both for that - I'll try searching for an Alldata CD over here.
I must admit I already have the WIS - but find it a real pain to work & not very user friendly when it finally does!
It's great - finally get a couple of sunny days over here & I'm driving around with the back missing out of my car!!
cheers
Chris

 

[bobterry99]

The hydraulic line you mention goes to a valve block Chris, (picture). Your car has two for the convertible top, and each has four solenoids. Power to the solenoids comes from relays located within the top control module.

Its possible that a problem with a relay or a solenoid is preventing your top from moving. But I believe it is far more likely that the control program hasn't progressed to the point of raising the top because the limit switch that detects when the compartment cover is open has a problem. This would be confirmed through diagnostics or by checking the signal from the switch with a basic electronic multimeter. You mentioned that no codes are set. But at the point motion stops if you continue to hold the switch long enough (up to 90 seconds) it should begin to flash -- this indicates a code is stored.

 

[Canex]

Thanks Bob, I'll go and try that now - I didn't hold the switch on for that long - I thought it might strain something!
I also haven't taken that side of the rear cover off - I thought there were only relays on the other side. I must try & get my WIS programme working!!
thanks again
Chris

 

[Canex]

HURRAH -getting somewhere at last!!

Hi all, thanks again Bob :thumbsup:- held button like you said & after 90 seconds finally got a code - 15
I have found out that code 15 means: limit switch soft top up (secondary closing speed)
Does anyone know what that means? or where the limit switch is situated?

It's almost exciting now!!

cheers
Chris

 

[lynns]

I see that Bob Terry has already been helping you but you may want to read the lower half of the page at http://www.benzworld.org/forums/r129-sl-class/1324795-r129-soft-top-controller-ultimate-thread.html

 

[Canex]

Thanks Lynn,
I have read them all at least twice - they are incredibly usefull - it's amazing that Bob Terry seems to have the answer to every problem!! I hope he can help me find the answer to mine!
I would like to say it's nice to get help from people you don't know, from all over the world! - I hope I can be of use to some of you in the future - I only seem to visit these forums when I have a problem
Out of interest have any of you got the cassette that came with the cars when they were new explaining how every thing works? If not I will try to get it on MP3 & post it.
Cheers
Chris

 

[lynns]

Out of interest have any of you got the cassette that came with the cars when they were new explaining how every thing works? If not I will try to get it on MP3 & post it.
Cheers
Chris

Chris, in the US I don't think we received an audio cassette when the car was new but I hope you know that we did recieve a left hand drive Owners Manual that can be found at http://www.benzworld.org/forums/r129-sl-class/1321546-r129-owners-manual-etc-download-site.html

 

[bobterry99]

I have found out that code 15 means: limit switch soft top up (secondary closing speed)
Does anyone know what that means? or where the limit switch is situated?

The limit switch you mention is "S84" and is located at the B-pillar on the left side of the car (picture). This switch is supposed to close when the leading edge of the top is at the front latches, and it signals the controller to reduce the force on the hydraulic cylinders driving the top. Your code 15 suggests to me that your switch may be stuck closed or otherwise damaged.

If the switch appears undamaged, then I would check its input to the soft top controller with a basic electronic multimeter. This post explains how to check all of the switches: ShopForum - View Single Post - hard/soft top troubleshooting question 91SL. S84 is wired to socket #28 of the "Y" connector to the top controller. When the top is closed, it shorts to ground; when the top is in the compartment, it is open-circuit.

If you have any questions about testing the switch or don't own a multimeter, then post back for further help.

Out of interest have any of you got the cassette that came with the cars when they were new explaining how every thing works?

The R129 Tech DVD from MBUSA includes manuals for all the radios that were installed over the years including the stereo cassette that you mention. If you have a specific question someone can probably answer it for you.

 

[Canex]

Hi,
I tried that switch & it's working OK - so is the one that signals when the deck is open. I think the fault 15 must appear because the switch S84 does not change because the roof does not go up to press it.
I can't seem to get a reading from the Y plug - I assume the other 2 need to be connected to the controller - does the ignition need to be on? and am I supposed to be testing the plug or the controller?
It's as if something isn't telling the relay to kick in or the relay is working but the fluid isn't getting to the rams.
Any more ideas please?
thanks
Chris

PS When I was talking about the cassette - I have one already - I was just wondering if I could send it to anyone who hasn't (if I can change it to MP3 somehow!)

 

[bobterry99]

I can't seem to get a reading from the Y plug - I assume the other 2 need to be connected to the controller - does the ignition need to be on?

It doesn't matter whether the other two are connected or not, but the Y-connector has to be unplugged, because the switches you will be checking are wired to it. The ignition should be off. You should have one lead of your tester connected to chassis ground and the other lead touching the socket of the Y-connector you are checking.

You may as well check all of the limit switches while you are at it. At the point your top quits if the windows are lowered, then the system is in "Position 2" mentioned in the post "ShopForum - View Single Post - hard/soft top troubleshooting question 91SL":

Position 2 (Top open but storage compartment cover open, windows and roll bar down)
Open: 16, 17, 18, 19, 20, 21, 23, 24, 25, 26, 28
Closed: 10, 22, 27, 29, 30, 31​

The numbers above correspond to socket numbers on the Y-connector (picture).

 

[msbarsi]

PS When I was talking about the cassette - I have one already - I was just wondering if I could send it to anyone who hasn't (if I can change it to MP3 somehow!)

Hi Canex and welcome aboard.
If I didn't misunderstand you, you want to convert the cassette to MP3 right ? If so you can look for a program called dBpowerAMP that pretty much converts anything into anything. The thing is that you have to connect a casette player into your computer line-in socket and actually record it in real time.
It will take you some time but you are done this way.

Cheers.

 

[RKH]

Hi,

PS When I was talking about the cassette - I have one already - I was just wondering if I could send it to anyone who hasn't (if I can change it to MP3 somehow!)

Please do convert and post it here. Our cars in the USA did not come with it and I suppose watching it is better than reading.
Thanks for offering.

 

[Canex]

Hi, I have tested all pins at the 'Y' plug & they are all as they should be in both position 1 & 2.
I am starting to think it might be the controller module (gulp)
I have checked at Y55 and there is no voltage when the button is pressed.
Are there any pins/connections I can short to bypass the controller?

Chris

PS - I can't find where my wife has 'filed' the audio cassette - I will let you know when I have found it.

 

[Canex]

Help anyone??
Bob - any ideas??

Chris

 

[bobterry99]

I have checked at Y55 and there is no voltage when the button is pressed.
Are there any pins/connections I can short to bypass the controller?

There are eight wires connected at Y55: four are grounds and each of the other four is a control wire for a solenoid. So, you checked all four with the switch pressed at the point the top should rise?

Bypass the controller...For what purpose? If it is to raise the top out of the compartment you could hot-wire the hyrdaulic pump and a solenoid or two, but it is probably easier to just lift it out with your hands.

 

[Canex]

Hi Bob,
I tried the connection at Y55 (Y55/4 I think - the picture you sent me earlier in this thread) which is the solenoid that pipes 70 & 72 go to & there is no voltage when the roof button is pressed.
I am trying to find where the supply to Y55 comes from.

I only wanted to short or bypass it to find out what part is faulty so that I can replace it.

cheers
Chris

By the way I am 8 hours in front of you here in the UK - it seems to take forever to get a reply!!