This is a topic that comes up fairly often so I figure others will find this useful.
When checking for parasitic draw on modern vehicles, you can not watch a live amp draw on the battery and then start pulling fuses like you did with the older generation of vehicles.
On modern cars, when you start pulling fuses, you will most likely increase the parasitic draw on the battery since other control modules may get "ausgeflippt", thus increase activity on the Gateway.
So with modern cars, you need to check for a mV drop across the fuses. VW released a Technical Bulletin (PDF) on this years ago and the fine folks at Bentley Publishers have it available:
Direct download:
https://wiki.bentleypublishers.com/download/attachments/83329026/vw.current.draw.tb.pdf?api=v2
Web page:
Parasitic draw testing through fuse panel VW technical bulletin 270711
It is very important that when checking for parasitic draw you follow the test plan as detailed in that bulletin when dealing with CAN Gateway cars.
When checking for parasitic draw on modern vehicles, you can not watch a live amp draw on the battery and then start pulling fuses like you did with the older generation of vehicles.
On modern cars, when you start pulling fuses, you will most likely increase the parasitic draw on the battery since other control modules may get "ausgeflippt", thus increase activity on the Gateway.
So with modern cars, you need to check for a mV drop across the fuses. VW released a Technical Bulletin (PDF) on this years ago and the fine folks at Bentley Publishers have it available:
Direct download:
https://wiki.bentleypublishers.com/download/attachments/83329026/vw.current.draw.tb.pdf?api=v2
Web page:
Parasitic draw testing through fuse panel VW technical bulletin 270711
It is very important that when checking for parasitic draw you follow the test plan as detailed in that bulletin when dealing with CAN Gateway cars.
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