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Old 03-20-2017, 05:57 PM
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patrickt patrickt is offline
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Quote:
Originally Posted by allcarfan View Post
I never could figure it out, nor could the shop.
Well that's a piss-poor shop that probably didn't want to go to the trouble of running voltage drop tests along the circuit, both on the hot side and the ground side. If you have normal voltage at the alternator/battery, and not-normal voltage a distance away, then you "walk the circuit," while it's under load, looking for the spot of increased resistance, with your ten dollar VOM, that will have a voltage reading when you bracket it with your probes. Voltage doesn't just vanish and fly off like Tinkerbell. It's slipping away because of high resistance, like a bad crimp, poor soldering, loose ground, or a broken wire inside the insulation. The only way you can test for it is when it's under load, and it takes a little patience. But it's not brain surgery.
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