[batmanandbobbin]

Someone did a hit and run on my wagon a few years ago in a parking lot (they only hit the rear bumper and the tailgate...no structural damage). When the car was repaired, the body shop replaced the tailgate with a new one and replaced the bumper cover and trim (wrong color: cream instead of grey like the rest of the car, but I digress). When I got the car back, the motor for the latching mechanism functions but doesn't do anything in terms of pulling down the tailgate once I close it. The tailgate closes fine when I close it (it closes all the way) but I don't know what to do about getting the latch motor to function properly? It makes the noises that it should (sounds good, not broken) and it runs when it should (when closing the tailgate and when pushing the button to open the tailgate). Is this difficult to take apart, diagnose, and repair? I have the Mercedes service CD's but I can't find anything on this part of the car. Also, the alarm system seems to be disconnected from the rear tailgate. The central locking works fine, but locking from the tailgate does not arm the alarm and if I try to unlock and open the car from the tailgate when the car's locked and alarmed, the alarm goes off. This is a real pain: I have to unlock and lock the car from the doors every time even if I only need to get into the rear compartment.

Does anyone have any images or shematics that would help me with these two issues? I have already taken off the rear tailgate trim and carpeted panel, so I can see/get to everything that's in the tailgate itself.

Thanks--

--James

 

[batmanandbobbin]

Lock and alarm

Found it. It was so simple. There is a 3 pin connector leading from the wiring at the lock to the wiring that evidently connects with the alarm system. It's held in a white clip in one of the openings of the sheetmetal on the inside of the tailgate. Whoever connected it back together thought that they had put this connector correctly back together again (instead, they put in in rotated 1/3 of a turn and the connector did not physically go together all the way or make contact between the two halves. I unplugged it, turned it to the correct orientation, and re-plugged it. Alarm's working now as it should.

I had to take apart the latch mechanism to re-connect a spring that had come undone on the latch pull-down. It's all fixed and my tailgate is functioning as it should. Thanks for the help.

--James

 

[batmanandbobbin]

Fixing the auto-latching mechanism

Wow...I wish that I had taken photos of the repair...I'm fuzzy on the in's and outs of what the mechanism looked like.

I'll try my best to recall what I did:

Remove the interior panel of the tailgate. Disconnect the tailgate lock knob linkage and linkage to the central locking unit. Unbolt the entire trunk latch from the tailgate and remove it from the tailgate.

The preceding part was pretty easy...here's where my memory is fading.

At first glance, there was a spring that was wedged almost in the middle of the mechanism. At first, I wasn't certain how this fit or where it came from

What I did was re-connect the electrical connections to the latching mechanism and I observed what happened when I manually closed the latch by hand.

If I remember correctly, what happens is the mechanism pushes a rod/bar that turns a starwheel that pushes the latch fully closed. The tricky part was figuring out exactly how the starwheel was turned because it looked like the bar was not contacting a flat side of the starwheel. I looked on the opposite side of the starwheel/bar assembly to see that there were several notches and holes into which the spring must fit to hold the bar in the proper position so that it contacts the starwheel when the latch is not fully closed. The spring was a little tricky to get into place, but I got it after a few tries: it's one of those situations where the spring's arms are held almost fully extended when the arms are in the appropriate holes/slots that hold them.

Sorry that I don't have more specific information, but it was a fly-by-the-seat-of-my-pants repairs and I didn't document anything. I would gladly take a look at some images if you take your locking mechanism out of the tailgate. It was such a pain to re-attach the interior trim on my tailgate that I hope I'm never going to have to remove it again. I'll take a look to see whether or not I did take photos...I remember that I did take photos of the alarm connection for the tailgate, but I'm not certain about the latching mechanism.

let me know if I can help you further...

UPDATE: I did, indeed take photos of the latching mechanism (with my BlackBerry, so img resolution might not be the best). I'll try transferring them and uploading them soon.