What does "Alternator reading at border line" mean?
Its on my invocie from mazda service.(Battery change)
I didn't notice that until i got home and its too late to call them.

 

Alternator creates the power for your electrical system and to keep the battery charged. It has to supply enough voltage and current to do the job. I would take the note to mean that your alternator is within specs, but just barely.

Are you using an undersize pulley, by any chance?

 

Nope.
I hope it's covered by warranty...