I don't know why it would be intermittent but I'm almost 100% sure there's a diagnostic port fuse you may want to check. It's in the fuse panel when you open the driver side front door, between the door and the dash.
Trying to use diagnostic computer/vag-com but no power in the port. Sometimes the the handheld will power on and then stop working days later, what sends power to the diagnostic port? Any ideas would be appreciated
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