Sprinter fuse

For Sprinter owners - there is a 20 amp fuse - I think it's a-23 that Mercedes has recommended to be replaced with a 25... This is in the starting circuit  and the mechanic just told me the new units are still coming through with the 20s --- I don't think its a big issue, but you might want to replace, or tell your mechanic...
Jack

What is this fuse for?   Has Mercedes put out an official notice on this?  Thank you.
Still must find why my Sprinter battery (under driver's feet) has a slow drain.   
It is a mystery.  Do not know where to go....Dodge?  Mercedes?  An auto electric shop?
Any input will be welcomed.   Do not want to have mega-hours on work order....just want it fixed so it can
be used.   Yikes...
Thanks again,
LRS

As I understand it the fuse is in the starting circuit, but not critical. I was having other work done and it was replaced - the mechanic said they were still coming through with the 20 amp
Anyway he replaced, yes, Mercedes has sent out a directive.
On your battery there's obviously a short someplace. I would go to a Mercedes dealer that services Sprinters - it should be under warranty if your rig is under 3 yrs ' 36k miles. More dealers
Are servicing sprinters since they are gaining popularity commercially.
Good luck,
Jack