Under Hood ACC Drain Access and Cleaning

Under Hood/Bonnet ACC Drain Access and Cleaning

Reference: BenzWorld Member, Les Smith, who checked the air intake under the bonnet. The drain was blocked and it 
 was full of water. This may have contributed to the corrosion and eventual seizing of his blower motor.

BenzWorld Member TuneTime says: open the hood. Look on the passenger side under the wiper. There is a large duct 
 with a grill on it. See the dirty hole in the bottom outer side all the way on the bottom. 
That hole gets clogged and the area fills to a point to which it spills over inside itself and enters the cabin. 
 So a visual inspection is usually fine, unless there is stuff in there. Then an air gun or a long screwdriver 
 to push the crap through is the way to go.

BenzWorld Member Adrian Mac says The lowest outside part of the car between the front and back wheel is a plastic 
 colour-coded sill cover. At each end of this are two drain holes, about 3mm in diameter and angled back towards 
 the rear of the car. I shoved a wooden kebab skewer up each one and found the front offside one blocked.
Inside the front wheel arch, near the bottom, there's a 10mm bolt attaching the front end of the sill cover. 
 If you undo this then the sill is just held on with a number of black plastic push-fit gromit like things 
 (the ones where the centre of them moves independently of the outside). Pull these off (by pulling out the middle 
 core first) and the plastic sill cover comes away. That's where I found two cup fulls of mud and dirt, blocking the drain.

Under Hood/Bonnet ACC Drain Access:

Under Hood/Bonnet ACC Drain Hole Location: