You are only feeling the return spring on each lever. If it's thinking of unlatching it will get very firm and resist moving.

Think of it like a ratchet wrench where you can't quite return enough to catch the next tooth it's a very similar situation.

I've seen it on xo numerous times.

The fact you got it to move enough to latch suggests you may get it to move enough to unlatch.

I just realized that you can see the top of the cable if you try hard enough though the rubber seal behind the door handle.

You can very likely get some penetrant into the top of the cable by poking the red tube in just the right place.

I've jimmied open a door with a broken DHC when I accidentally left my key in the car. I pushed on the cable with a screw driver to pull up on the cable.

You could feel for the cable to figure out where to spray then madly operate the door handle to work the penetrant down the cable. If that is the problem (80% chance my estimate), you should not only be able to get there door operating you can also pull the access plug out of the door edge after you get the door open and I think you can even get a better shot at the top of the cable.

BMW added a rubber nipple at the top of the cable to reduce water getting in which will unfortunately make it a little harder to get the penetrant in but it should work in.

If you can get the door open and access the top of the cable from the side you won't need to even take the door apart. (also do the same treatment on each door. Light penetrant only no oil).

I need to refurbish a DHC on my car if I get a chance I'll see if I can get a pic with my fiber optic camera to show what I'm talking about.

You may also be able to spray the top of the cable down along the outer window seal but I think better bet though the door handle when lifted

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2011 E70 • N55 (me)
2012 E70 • N63 (wife)