Need some help identifying a strange box in my engine bay that seems to have a lid hanging off

Its on a UK Spec Mk3 Titanium navigator Sept 2013 1.6 Duratorq tdci diesel

Its immediately behind and below the passenger nearside headlamp (you can see it looking back down the slot at the rear of the headlamp. It apears to be a plenum of some sort with a tupperware like lid vertically at the rear and a electrical connector with a sky blue cover at the front. Sixe about 12cm wide by 20cm down

I droped somethng down the gap when playing and while trying to see where is was (right at the bottom on the undertray as normal), saw that this lid is half hanging off this plenum. Took light cluster out and tried to clip it back, but doesnt stay, so I taped it with insulation tape. The rear faces the wheel arch liner so I think I will have to drop this out to get to it as I can only get fingertips to it from the headlamp side

Cant find any reference to this plenum and its not attached to the air inlet

Any ideas

Thanks

Stephen

Post up a photo and we'll see what it is for you.

Will do when it's light enough

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