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Unfortunately testing it with a test light went out about 25 years ago. Starting in the mid 80s vehicles starting using computers that when the vehicle is turned off they need to consume some electrical energy in order to "go to sleep". The resistance in the bulb of the test light doesn't allow enough energy to flow through the control module to allow the control module to perform it's functions necessary before it can go to sleep. The best way to test it is using an amp meter with a 10 amp scale. The "old school" standard used to be 1/10 of an amp or 100 milliamps draw as being acceptable, modern vehicles you want under half that or 50 milliamps and that is after about a minuet or two. This year/model VW should typically draw about 2 amps when you first hook up the amp gauge and drop down to about .04 amps (40 milliamps) in a minuet or two. You can work around not having an amp meter and using the test light if you follow this procedure. The disadvantage is you won't get a value reading in amps to know exactly what the draw is. Try this; With the negative battery terminal loose, but still connected leave the vehicle sit with all consumers off for about 5 minuets. Now hook up the clamp of the test light to the battery terminal, place the point of the probe in the center post of the negative post of the battery, then gently lift the terminal off the post until only the test light is between the terminal and post. See if the test light is illuminated using your old standards. Again its best to have the amp gauge that way we know exactly what we are dealing with. Let me know how it goes and we'll take it from there.