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post #6 of (permalink) Old 03-22-19, 08:25 AM Thread Starter
DaughtersCar
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Join Date: Mar 2019
Posts: 4
I checked the voltage drop from the battery to the alternator small connector (pin 3), no voltage drop. Also verified 8 volts on pin 1 with ignition on, engine off. As far as the input circuit to the PCM on pin 2, I just checked resistance to ground since I couldn’t find a pin-out for the PCM. It was 6 megohms, and didn’t vary all shaking down the entire harness from the alternator to the PCM, so I had to assume it was good. Since the original alternator didn’t have the “after 30 seconds battery light” issue (remember, it just wouldn’t provide charging voltage unless I gave it 3000+ RPMs), I removed the newly installed “remanufactured” alternator and installed the original. Started the engine and gave it enough gas to get 13 volts to the battery. Battery light never illuminated. So the reman alternator had to be bad, right? I took it back where I bought it and explained all this to them, and they refunded my money. I then located a brand new alternator at another parts store and bought that one. Put it on, and it charged the battery with 14+ volts and no battery light. Problem solved, thanks for the input.
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