Originally Posted by BigBody

People report bad alternators with the light on, & with the light off. Must be a specific condition to set off the light. In my case, i believe the car would start & the alternator was lazy; not running. With the engine running it should be at or around 14v. Use the OBD menu so you can get an idea where the voltage of the battery is while the car is off, cold, driving, etc.

Once i changed the alternator my problem was completely gone. The bad alternator eventually killed my battery (seems your having a similar problem), thus leading to my car dieing on the bridge. Luckily i was over the crest, but yea... just nothing- hazards wouldn't even blink. Rolling with nothing but the machine lol... my mother was close by, jumped the car & guess what? Car ran fine all the way to the BMW event in the bronx we were heading to hahaha...how ironic... yea id replace the alternator & battery while you're at it.

BTW, if you have an '05 4.4i, you probably do have air suspension, just in the rear as opposed to 4 corners like in the 4.8's.