Assuming it is like the one on my SD, you have a hook mounted to the top frame and on the door you have a box shaped striker plate which raises up when the handle is lifted and releases from the hook. Probably, the box is not retracting so as to catch the hook. Try pushing it down with your finger and spraying a little lubricant in the opening. Or, the hook is not hitting the box in the right place, or the hook is broken off. This isn't rocket science. You will just have to fool around to find out the problem.

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'76 240D-Sold
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'06 E350 Wagon, 84K Miles
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