Hello all,

I am working on some issues on my partner's 2008 ML350 and just want some insight before I dive in. My main concern at the moment is the sunroof as the trunk is somewhat of a known issue that I think I have a handle on.

So to go along with the sunroof issue...I had to disconnect the battery a little over a month ago to replace the rear SAM and taillight seal due to the old one getting soaked and making the car go absolutely bananas during a rain storm. Luckily the SAM issue is completely fixed, I protected it really well and replaced the taillight seal (which was brutal) and all works as it should. It also removed some of those random tail lamp errors that he kept getting on the dash. After reconnecting the battery, we had a really hard time opening and closing the sunroof. I reset it and synced it up and now it seems to get crooked and the motor sounds like it it skipping teeth. When closing, if I push the wind deflector down it will close the way it should. I did check the tracks for debris and found out that there were two small plastic pieces keeping the deflector from going down. I removed them and still have to push the deflector down to get the sunroof to close. I spoke with MB about it and they said it is an almost $3000 repair to have the motor and tracks replaced. I want to try the whole situation again and was told to grease the track really well with lithium grease to see if that will help with getting it to open/close smoothly. I do think I need to replace the motor too because one of the gears sounds like it was stripping out. How hard is it to replace the motor?

Now to the trunk. When my partner got the car the auto trunk did not work at all. Found out that the pump was corroded and ruined so I replaced it and it worked extremely well. Now it will open on its own but does not want to close on its own. I have fiddled with the pinch sensors along the edge of where the hatch lid closes and most times after pressing on them, etc, I would be able to get it to automatically close. Now it won't close by itself at all and I am almost positive it is the sensors which sadly are very hard to come by as they are discontinued by MB. Has anyone attempted the resistor bypass so the computer thinks the pinch sensors are working properly? I have an entire box of resistors, those being 3.9K resistors that I have seen people use with success. Where is the connector where I have to install the resistor to bypass the pinch sensors?

Thank you all!

-AW

 

For sunroof, use a scanner (with Mercedes option), and try adaption. That may resolve the issue.
For the trunk issue, I'm pretty sure it's the actuator module. It heppened to me couple of times. It's the module next to the hydraulic pump under the trunk floor close to the tailgate. I got the module from a junkyard a few years back, it's still working.
You should be able to find some videos on Youtube related to changing this module.
Good luck.