Without even knowing the amp rating of the motors , it would be a safe guess that the 5 AMP fuse is more likely the correct one. 12 Volt motors use high amperages, but 15 is overboard.

If it is a short, a 15 Amp will blow anyway. If it is just a bad motor, replacing the 5 amp with a 15 won't solve the problem. You could try it and see first.

I would still suggest it is a 5 Amp fuse in that application. I checked mine and it is a 5 AMP. Mine is in compartment 36, not 6. Page 240 in my 06 roadster manual.


roadster with a stick