E55 W211 Electrical plug for the rear air strut (airbag) won't clip in

[davidmudley]

I have come across an unusual challenge while changing the rear passenger side suspension airbag (right hand drive), and that is not being able to plug the power clip back into the new OEM airbag. It is the same part number and identical the one that used to be in there but for whatever reason the plug goes in and seems to sit nicely, but it doesn't catch onto the latch to hold it securely. There doesn't seem to be anything impeding it, and it's all clean. I've also tried applying a little force to 'encourage' it to clip in but that doesn't help.

I've since removed the new air strut and put the old one back in again to see if the cable plugged in easily, I noticed that it is doing the same thing (not clipping in securely), it feels like it is seated but not securely clipped in, and can then be pulled out with a gentle pull.

The plug that I am referring to is the one that provides power to the airbag / air strut, I've included some photos below.

Anyone come across this before? I'm at a loss as this should be the easy bit in the airbag replacement process!

 

[flying haggis]

it looks like the plug doesnt quite match the socket, in the plg part on the airbag there are two ribs at the 11 oclock and 12 oclock position in the photo but I cant see a corresponding slot in the socket

 

[Jobsworth]

There is a rubber seal in the bottom of the plug that seals it when it’s firmly into it’s socket. The rubber sometimes swells a bit or gets a bit dry and it becomes reluctant to slip in and holds the plug out. Spray a touch of WD40 into the plug and see if that helps

 

[davidmudley]

Thank goodness! The blowing of compressed air and some WD40 did the trick, though it still took some fiddly and pushing the clip down over the retaining bump.

All good now.

Hopefully with any luck I can now put the other bolts back in and get the car pumped.

 

[davidmudley]

Success, the car is back together and all is well in Merc land.