A test light is useless on a newer vehivcle, there will be a drain but the test light cannot tell you if it's too much.

You cannot use voltage to test for a drain, you have to set your meter up for current measurement. I will offer, one more time, to tell you how to set your meter up to read current if you will me what make and model meter you have. The current draw test is very simple and a meter will give you hard numbers to use in comparison.