[TopDown]

Have the BMW Advanced Battery Charging System - not the version with alligator clips, but the version with cigarette lighter adapter. I've used it to charge my M Roadster with no problems.

I tried to test the ABCS on the wife's 335i Coupe, but the unit indicated a bad connection. After a little troubleshooting, I confirmed that on the 335i Coupe the cigarette lighter is not hot unless you turn on ignition (or leave the key in). Note that the Z4 cigarette lighter is always hot.

So here's my question; can this version of the ABCS be used on the 335i Coupe, or can you only use the ABCS with alligator clips?

[tintivilus]

You can use the cigarette-lighter ABCS just fine if you wire in an always-hot lighter socket, or you can just cut off the lighter plug and put on some clips.

Your only problem is that you can't charge the battery through an outlet that's disconnected

[TopDown]

Found the Solution at Radio Shack - a female lighter unit that's connected to a pair of alligator clips. Works perfectly.