Quoted from PhilGreg:So here's for issue #2
If you have one of those wires where the solder just let go, you may very well have others. You might consider carefully, methodically and gently tugging at all of the solder joints, one at a time. Don't be surprised if a couple others pop right off in the process. While you may think that you've made things worse, those joints probably are or someday will be intermittent.
If you found a loose lug nut on a wheel, would you check the others?
/Mark