It's 10 ga so the complete harness melts down with a short instead of just it!  ;-)  

It has more to do with the need for a mechanically strong wire coming off the alternator, which moves and vibrates a lot, and the engine compartment is hot. It powers everything on the engine plus the ECU, so if it breaks you are dead in the water.

Stuart

-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of Gene P
Sent: Wednesday, February 10, 2016 3:05 PM
To: vanagon@GERRY.VANAGON.COM
Subject: Re: PS pump switch, engine compartment wiring harness

Alternate take:  The wiring diagrams are always challenging, but looks to me like that red wire in the box, and also the feed from the Alternator to the box, are both 1.5 metric.  So 12 gauge wire would be a decent upgrade.
Why would you need a 10 gauge wire on a circuit with a 7.5 amp fuse?

A simple FLAPS fuse holder should be fine, you don't really need the weatherproof caps up inside that wiring box, and working space is scarce.
Stuart MacMillan <stuartmacm@gmail.com> "Red wire is 2.5 metric, 10 ga AWG per Bentley. Best to get a holder with 10 ga pigtails and use appropriate butt connectors."