[IN54NITY]

Thread resurrection..

My alternator went out at mile 82k, with the aforementioned "red battery" warning. With the help of MrVedit (a forum member), we replaced the alternator ourselves. I have the Bentley manual as well and followed its directions (as mentioned in post #2 of this thread) until it came to loosening the AC compressor. It's near impossible - and I even had the privilege of using a lift - to get the third and final bolt to loosen the AC compressor. The Bentley manual makes this sound trivial, but it's not, so I wonder if it has to do with exact year/model. I have a 2009 N54 XI with stock oil cooler. I gave up trying to loosen this third bolt, so I ended up loosening - but not completely removing - the intake manifold (as Sikh335xi mentioned two posts above - but I did not cut off the OEM air filter attachment point) - and the oil filter housing. A real PIA because a water hose goes in there and you don't want water/oil contamination. I ended up replacing the oil filter housing gasket (to block) and the serpentine belt as well. Here's a pic of the alternator regulator/brushes/ring contact. The bottom copper ring was completely gone, the brush for it was toast too.