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Old 12-09-2012, 12:52 PM   #17
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Location: Loveland, CO
What I Drive: 2002 Red Wagon

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From my recent experience, the top two suspects for me would be the accessory plug on the alternator (3-wire connector) or the positive battery cable. Oh, make sure you've cleaned the ground connection wires, too. When I had Advance Auto test everything, they told us the same thing: both the new alt & the new battery were fine. Their test equipment simply isn't the right stuff to trace the problem down.

In my case, I replaced the connector first & still had all of my problems. Taking it to an automotive electrical specialist (in this case, an R/V retrofit guy) gave me a way to test the entire system ($80). This provided him the info to determine that the positive cable had enough broken strands that it was killing both the alternator & the battery. He cut off the old terminal clamp & soldered on a new one.

All of our electrical problems were finally solved with that fix. If you don't want to keep guessing, find somebody with the proper test equipment.
"Help, Mr. Wiza-a-ard!!"
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