Switches on a Terrano 1990
 

Hi, I have a LHD 1990 Terrano 2.7TD and no user guidebook, there is a switch, a pull switch in fact that is under the dash on the left side of steering wheel not far from fuse box, it has an outline of an engine block on it and pulls out in a click about 3 times, I have no idea what it is , can you help please??