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Old 06-02-2018, 07:29 AM
Witsend Witsend is offline
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Join Date: Nov 2012
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Witsend Made it to level 2!  Looks like you are on your way to becoming famous


Weird, a Correct 4G alternator installed on the 03 Grand Marquis, Low charging voltage at alternator stud, no missing humps in pattern, still maintains slightly over battery voltage at idle with high speed blower on, Hi beams, and rear defogger on.
PCM desires 13.9 volts yet sees there is low voltage but not setting a charging system fault , or turning on the battery warning light.For interim I think I'm better off with the alternator from the 01 Crown Vic and put tape over the battery lamp .I don't like the strange unicorn hump on this 4G one though, hmmmm? Guess it's time to actually pin test the rectifier connector back to the PCM connector , can't account for more than a half volt difference the PCM reads battery voltage as 12.06 V and I'm measuring 12.95V at the battery. Maybe this used 4G alternator's regulator is just Wrecktifried?
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Last edited by Witsend; 06-02-2018 at 07:59 AM..
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