Electrical Gremlins

[capt_casual]

Hi, Yall
I have an 02 F-250 7.3l extracab which I purchased from the first owner apx. one year ago. I am very happy with the truck, it's a great hauler and super comfortable for long trips.

One small issue, which I fear is becoming a big issue, is some curious faults in the electrical system. Since I bought the truck I noticed the radio would occasionally not work, this might happen at initial key-up or at some point down the road. Often it would come back on after a random period of time and sometimes it would not. If the headlights are on the radio will display the clock. This is not a huge deal for me in and of itself, I can live without the radio, but when the radio cuts out the power windows are also non-op.

Is there a relay or other point in the harness where these two circuts are common?

So these two ckts failing are a nuisance but not mission critical. Yesterday the stakes got higher and nearly required a cab ride home. I put the key in the ignition and paused while the fuel pump primed, as I recall the radio worked at this point, when I turned the key to crank the engine I heard a faint "pop" from the fuse panel and discovered a blown 30amp fuse at the "starter motor" position (103, I think). I robbed a fuse from another non-essential ckt, took a quick look at the starter motor to make sure everything was tight and right, then tried again. Two fuses down. I replaced the fuse again, turned the key to "start" and was pondering the situation for a bit when the radio suddenly came on (I hadn't realized it was off) and I thought; hmm, maybe... sure enough it cranked and started.

I guess now I'm looking for a place where all three (radio, power windows, and starter motor) circuits are common, right?
If I need to wring out the harness do I have a resource for routing, color coding and test points?

Thanks in advance

[NoRalPh]

Have a look at the Fuseable Links that feed the fusebox. There is a connection that's problematic with corrosion on an '02....

POTENTIAL ELECTRICAL CORROSION if your truck is like mine......

It's also no uncommon for that sm wire on the starter to be chafed through, under the insulation that protects the connector at the end, and shorts to the started body. You can just bend it away to be sure.

[capt_casual]

good steer, I'll start there today and keep an eye on the other thread as well. I will post my findings.

[capt_casual]

The fusable link connection at driver side fender well checks out OK, everything dry and tight. this area does seem rather exposed to be the home for relays and din connectors but there does not appear to be a smoking gun here.
Is one of these relays common to the faults I have described? does anyone know where can I find schematic drawings for the electrical system?