I have a 2009 s550 4Matic (Since I am in the US it is long version). Recently, I started noticing my trunk wasn't working correctly.
The issue was in the following: after each car wash, my trunk would open but wouldn't lift up or down with the press of a trunk "Close" button on a tailgate. After few days it was ok again. But after the last car wash, the trunk stopped lifting up or down at all, and tailgate "close" buttons were not lighted up.
I took all the interior out and checked the right side of the trunk where the hydraulic lift motor is located. Not surprised; everything there was wet. There is this "case" that holds a hydraulic lift motor(on pics I am attaching it is on a left side from the red circle with white zip tie around), and it has this kind of industrial foam. It was soaking wet, then the logic board where this motor is connected was also wet(including connector and board itself). I had a leak between the right taillight and body panel, did some magic there, hopefully, fixed.
With the amount of rust hydraulic lift motor had, I assume that leak was there for a while, even before I got the car(I got it in August of 2020).
Dried everything up, put it back together, and - nothing...
The logic board receives 12V, but I am not sure if it gives out power. I used a multimeter to check the pins where the hydraulic motor connector goes, and while pressing tailgate "close" buttons, it kept showing 0.
I am seeking some help to identify this logic board and where I can get one? I will give this one to my friend, and he will try to work with this one and clean it(I think water created some oxidation/corrosion).
But if this won't help, I will need a new board; motors are not expensive, up to $100 on eBay, but before buying that want to check if the logic board could be an issue.
The front white cover of this logic board only has "080808" on it.
Thank you in advance! This is a pic when I just removed a trunk liner, and you can see water on my fingers that were on, in, and around that board and connectors. This is the location of that logic board I need help with. Some corrosion or oxidation.
At this point you have nothing to lose by trying a cleanup of the board itself. I've done this a few times on electronics that have been wet. I've done this with remote key fobs that have been through the washer and dryer. I've done it with a couple of keyboards that had stuff spilled in them, and one or two boards that were affected by water leaks. The first time I tried it, it was a PC motherboard that had a glass of iced tea spilled on it... while it was powered on. So far, so good... I have been 100% successful. Your results, of course, may vary.
Water itself won't damage anything on that board. Corrosion, oxidation, and mineral deposits left behind from getting wet and drying out can and will cause problems. The goal is to get the board CLEAN and DRY. I've used detergent, like like a drop or two of Dawn for dishes, along with a soft bristle brush. I usually use a disposable acid brush with the bristles trimmed to about 1/4 to 3/8", but a soft toothbrush is OK too. Get the board wet, and gently but thoroughly scrub to remove all foreign material. Rinse with tap water, then rinse again -- thoroughly -- in distilled or deionized water. I actually just use filtered water from our fridge.
I usually dry them in a warm (not HOT) oven. 150 degrees or so is plenty. You just want the board to dry thoroughly. As an alternative, you can shake it dry and drop it in a bag of rice for a few days, or use a Ziploc bag big enough to hold the board and a bag of desiccant like silica gel. There's more than one way to do it, but the object is to get that sucker thoroughly dry before trying it out again.
Sounds crazy? Not really. Not when you understand the physical properties of the board and the components on it, AND understand that at this point you have a board that doesn't work. You can toss it i the garbage, or you can try to clean it up. If you try and fail, you're lost half an hour or an hour of your time and are right back where you started. If you try and succeed, you save the cost and hassle of finding a replacement that, if it's used, may or may not work anyway.
At this point you have nothing to lose by trying a cleanup of the board itself. I've done this a few times on electronics that have been wet. I've done this with remote key fobs that have been through the washer and dryer. I've done it with a couple of keyboards that had stuff spilled in them, and one or two boards that were affected by water leaks. The first time I tried it, it was a PC motherboard that had a glass of iced tea spilled on it... while it was powered on. So far, so good... I have been 100% successful. Your results, of course, may vary.
Water itself won't damage anything on that board. Corrosion, oxidation, and mineral deposits left behind from getting wet and drying out can and will cause problems. The goal is to get the board CLEAN and DRY. I've used detergent, like like a drop or two of Dawn for dishes, along with a soft bristle brush. I usually use a disposable acid brush with the bristles trimmed to about 1/4 to 3/8", but a soft toothbrush is OK too. Get the board wet, and gently but thoroughly scrub to remove all foreign material. Rinse with tap water, then rinse again -- thoroughly -- in distilled or deionized water. I actually just use filtered water from our fridge.
I usually dry them in a warm (not HOT) oven. 150 degrees or so is plenty. You just want the board to dry thoroughly. As an alternative, you can shake it dry and drop it in a bag of rice for a few days, or use a Ziploc bag big enough to hold the board and a bag of desiccant like silica gel. There's more than one way to do it, but the object is to get that sucker thoroughly dry before trying it out again.
Sounds crazy? Not really. Not when you understand the physical properties of the board and the components on it, AND understand that at this point you have a board that doesn't work. You can toss it i the garbage, or you can try to clean it up. If you try and fail, you're lost half an hour or an hour of your time and are right back where you started. If you try and succeed, you save the cost and hassle of finding a replacement that, if it's used, may or may not work anyway.
Yeap, that’s what I think my friend will be doing.
But thanks a lot for response.
In meantime still want to find that board in case this won’t work.
