I have a 2004 Jetta TDI Auto Sedan. I have had the recall to have the 7v ceramic glow plugs replaced with 5v steel glow plugs + ecu update. There was a recall for the recall because the 5v glow plugs have issues starting in cold weather. Then recall expired. I have bought the 7v glow plugs plus the controller. I want to update the ecu to 7v glow plugs. I understand that I need to do a BDM read and do a backup and find a dump from another ECU that has this update then compare the files? Maybe someone who has done this before can point me in the right direction.