have a 2002 ML320, been working on replacing the driver lock actuator. I can't get to the 4mm hex screw to remove the cylinder. the shaft of the 4mm hex key is 4", I thought this would be long enough. But it feels like something is blocking me from going straight in. SO, either there is something in the way, or the key is not long enough.

Any thoughts on this? Did anyone have any issues in removing the 4mm hex screw? Videos on youtube show nothing to be intrusive.

Thanks,
Maneesh

 

I just did the front passenger door on my 2001 ML320. It's a bit fiddly to find the right position, but I had to insert the shaft a full 5 inches to engage the bolt.

 

I bought a 9" one from Amazon (no one else had any long shaft hex in stock and shipping would be a week out), got it delivered the next day. Used it to unscrew the bold and remove the cylinder. Worked well. So I guess a 5" plus shaft is needed. The 4" from Harbor Freight was not long enough or barely touched the black plastic part surrounding the screw.