New Alternator and battery - low alternator voltage

2003 FORD EXPEDITION
65,000 MILES • V8 • AWD • AUTOMATIC
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DPCAXX
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I have tried two different alternators with the same results... the system wont come above 12.1 vdc and the battery indicator is on. The engine stalls when the battery is disconnected. Its like the alternator is not being told to turn on...is this a PCM problem? I cant find a "alternator" fuse
Jan 9, 2010 at 3:12 PM
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RASMATAZ
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Check fuse no. 9 10 amp in central junction box behind right kick panel-If okay could be the computer control of the field generation driver circuit.
Jan 9, 2010 at 5:05 PM
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DPCAXX
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Fuse location 9 is a blank...no contacts. Someone suggested that the output from the PCM may be bad. I have 9vdc and 13 vdc coming from the PCM to the alternator. Anyone know if this is the right voltage?
Jan 11, 2010 at 9:12 AM
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RASMATAZ
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I think the fuse location is mixed up is should be #f1.9 in the engine compartment fuse panel. Here is the location.
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Jan 13, 2010 at 11:43 AM
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DPCAXX
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That did it all fixed thanks for your help. I love this site.
Jan 13, 2010 at 2:49 PM
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