RCD330 headunit battery drain question

[onewatt]

Hello everyone

I decided to do a headunit upgrade on my Passat B6 2007, and went for the RCD330 with Apple car play, these are fantastic and a straight swap for the factory fitted radio,

I read a lot about battery drain and canbus etc and the guy who sold it to me (from China) said that If I use the special adaptor lead he also sold me for £27 it would stop the issue , it has I believe a canbus decoder or similar in it

Anyway I’ve fitted the stereo and I’m very pleased with it , my question is this, does anyone know of a simple way to test and be sure I don’t have the battery drain issue ? The stereo turns off with the ignition which is encouraging , and if left for a while it displays the “welcome to Volkswagen” start screen when I put the keys back in which again is encouraging, but if I get in my car without putting the key in the ignition I can just turn the radio on , not so encouraging ,

I’d just like to find a way to know for sure if the battery drain issue is resolved or not , any suggestions please ?

Many thanks