Layback40 had the right idea. Wiring will ohm out okay if you have all but 1 stand of wire broken. Doing a voltage drop test will reveal high resistance with current flowing - something a resistance check requires none of. Corrosion in the wire could have contributed - peel the insulation 3 or 4 inches and see if the copper has turned green or is white with powder.

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Thanks,
Mark in NC

"Spark plugs?...We don't need no stinking spark plugs!"
1985 300SD "Der Silberne Schlitten" 420,000 mi


Wish these were diesel:
2003 Ford Club Wagon 130,000 mi