Never noticed it before but as I pulled up at work this morning the fans came on and the dashboard dimmed. Voltage on dash at idle with no lights is 14.1, this drops to 13.6 with the light on, and 11.9 when the fans cut in. Seems like quite a drain? I don't recall such a dramatic drop before. I have a power commander ready to go on and use a heated fleece in the winter so the battery health is fairly important, its about a year old, one of Griff's ones.