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Topic: Dead Short under U300 Dash, Almost (Read 479 times) previous topic - next topic

Dead Short under U300 Dash, Almost

Yesterday I kept hearing a clicking noise under the dash of my U300.  After searching out the source it turned out to be one of the four 15 amp, self-resetting breakers above the steering wheel between the large fuse block and the small fuse block left of the relays. The breaker to the far right was the culprit. I bought a new breaker but the problem continued. It appears that the 12 ga red wire coming out of the breaker had a load much larger than 15 amps. It almost acts like a dead short but no fuses blow. I now have that wire disconnected but I can't find what it powers so I don't known what needs to be fixed.

I have searched through the schematics, I'm fairly competent at reading them, but cannot find those four 15 amp breakers to see what that wire powers. With it disconnected I haven't found anything that doesn't work. CAN ANYBODY HELP ME.,

Re: Dead Short under U300 Dash, Almost

Reply #1 –
Kent I will look at mine and see if I can figure it out .
 

Re: Dead Short under U300 Dash, Almost

Reply #2 –
Kent,

I'm looking at my 12 volt schematic (B-2037).  There is the horizontal row of boxes (near the top) listing all the blade-type fuses.  At the left end of that row, there is a box with 8 "contacts" inside it, but no labels.  Under the box, says "SEE DWG A-4845".  3 of the contacts are powered off the "IGN" side of the main ignition solenoid, but doesn't show where they go after that.  The bottom contact (wire) leads off to another reference to DWG A-4845, and DWG  B-2126.  Going to my drawing B-2126 (automotive wiring) I see that wire (C6 RD) goes to the 30A ATEC breaker, and from there to a 90A breaker.

Could those be the doohickies you are looking at?  No idea what they are used for...