Ken Ngo

2011 ML350 4Matic gasoline, My VIN: 4JGBB8GB8BA659767 about 140k milage

While I removed my air intake manifold to for P2004 code, I saw a hose without any connection hanging above what seems to be the exhaust manifold. Is it normal to have this hose here? I just want to make sure that the previous owner didn't mess something up in this area or I disconnect this hose from something and did not remember.

Plutoe

look here----Mercedes-Benz Electronic Spare Parts Catalogue Online

Maj. Dundee

That is the Thrans. vent hose and is supposed to be open on one end.

E55Greasemonkey

Actually it's the vent hose for the ISM on the side of the transmission. It's placed high up there so if you're driving through deep water it stays dry. The question I can't answer is why the ISM needs a vent hole?

Solo wing

I wondered the same. Perhaps the ISM gets hot and needs some kind if ventilation?

Holy ****
Just mentioning ISM again brought back memories from when it failed. The AWD was completely locked and towing it was hell.

E55Greasemonkey

There's an electric motor in there. Perhaps the vent prevents the sparks from causing the unit to explode. lol.