One of the reasons I used a timer relay on mine is because it is an 02 model and the light is not interconnected...i.e., the light is on when the ignition is on, and through the start cycle. Also, the 2002 model and I think some older ones, have had some starter issues, mostly due to weak batters causing kickbacks and breaking stuff.... especially when hot. As a result, I want "all" the power for starting and not for lighting when I hit the start button. As far as using a relay, well, that's exactly what this is... a relay that I just happen to be able to adjust for when it comes on. There are a few other "technical" reasons to inhibit or limit immediate battery use immediately after starting, but in this application they don't amount to a hill of beans.