Looking for info

[oil_man1]

Hi... Just purchased a 05 SUT from a dealership and having trouble figuring out what one of the buttons is for. It is a round button to the left of the steering wheel and right of the light controls. It is a toggle type switch with a (l) on the top position and a (ll) on the bottom toggle position. I have read the owners manual front to back and can not find anything about this switch. I am guessing something aftermarket but it looks factory installed... Any help would be appreciated ... Thanks, Les