Electrical issue and solution

[John From Detroit]

Had a "Fun" one yesterday.. Noticed power to my Engel Freezer was absent. Checked no power to the power 12 volt power strip (it normally runs on 12v) when I pulled the feed line to the stirp I had 10 volts,, TEN VOLTS?  Putting a small load on it (An LED lamp, one LED) the voltage hit zero and fast. 

Switched to 120vac for the freezer and went to bed.

Got up this morning.. Re-did the ground lead on the battery, it looked ok but in truth was getting to the point where failere was going to happen, (Not there yet) cleaned and polished while at it (Thia is a 10ga wire hooked direct to the house batteries back when the RV was pre-delivery)

Checked the positive lead, Good solid, 13 vac measured when I piereced the wire load side of the fuse.

This is one solid length of wire, no joints, 10ga "ZIP" cord, from the battery to the power strip....  (Rig Runner power strip)

Started testing at assorted points. All good till I got to the photo.

This was perhaps 2-3 feet from the battery connection,  The 'Nick" in the insulation you see in the photo is fresh, I put it there to confirm this was the problem spot. 

When I cut the section out I found the wires much tarnished,, When I cut back a few inches on each end and spliced (Solder method) the system now works fine  So problem solved.

But I've never seen this in the middle of a span of wire before.. I mean on an end where chemicals and weather and such can get at it yes, but in the MIDDLE!!!.

See photo.

 

[denmarc]

I have seen something along these lines many times before.  As a truck driver in MI., I have driven through many winters associated with road salt and the like.  You know what I'm talking about, John.

Many times I have had the mechanic trace a wire problem where it was nicked/worn in one particular place, and found the "weak link" a couple feet away down river of the nick/worn spot!  Migration of the water, I guess.

Wicking in your situation?

 

[John From Detroit]

IT would seem to me that there should be evidence of corrosion along the wick path, 3 inches away (Either direction) the wire was bright and shiny, looked like brand new.

I"m just glad I found it.

OH, and this ride has only been driven in a Michign winter one time,, SOUTH, as quickly as possible.. and it was raining that day, No salt.

Rain... IN January. IN Michigan.

I'm just not used to seeing it in the middle of a wire.

And the ice cream is frozen again .. Glad of that too .

Now I got to re-program one radio since it lost it's mind (oh well, that happens).
(The other radios up there have non-voiltle memory)

I also sealed all the test points I made (GOOP, great sealant, does not seem to bother the wire, and it sticks like glue.. of course, it is glue)