I'm trying to diagnose a 05 chevy express 2500 4.8l that keeps blowing fuse #30 for the aux outlet. It blows the fuse evey week sometimes up to two weeks. It will occationally blow fuse #29 for the driver side aux outlet but it has only blown that one 1 time in the past year. The customer has had this issue for about a year now and also said that the charging time for his cell phone has dramatically increased from both outlets since this has started occuring.

What I've tested:
When I install a new fuse I get 12v to both sockets.
Ground circuit has .2 ohms of resistance from socket to body ground.
Tested resistance through wire from fuse box to outlet: .4 to .5 ohms (which seems high).
Checked the ground G304 under passenger kick panel: It's secure
I've wiggled the wires while testing for resistance and the numbers stay solid
I swapped the socket from left to right and still only the fuse #30 for passenger side outlet blows.

From here I don't know where to go, I'm almost leading to a internal failure in the fuse box. I can't confirm the "slow charging" the customer stated and that's the only thing I have linking the two sockets together. The fuse box and the ground point are the only place where these share componets.

Any ideas from here? I've heard that the sockets go bad but I figured swapping them left to right would eliminate that.
.4 to .5 ohms of resistace seems high for the wire from the box to the outlet... do these fuse boxes develop corrosion intenally?
Thanks ahead of time!

 

Wondering if you solved this issue.