no he is right.. it has something to do with the tach signal.. i heard the same thing.. i was going to post earlier..cause i knew what you were talking about without the picture.. i forget what it is.. and YES there is a SMALL chance i am WAY wrong.. but i was told it is tach signal.. maybe diagnostics??? ability to see revs while under the hood? just a wild guess.. but im pretty sure something with rpms signal...