Battery not stay charged

2011 DODGE DURANGO
70,000 MILES • 3.8L • 6 CYL • 2WD • AUTOMATIC
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KAYKONES45
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Hello, i changed the alternator and replaced the battery and it still will not keep the charge. i was told it could only be the ECM. is that correct?
Jan 2, 2019 at 8:41 AM
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ASEMASTER6371
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Good morning,

Yes it is possible.

Did you verify voltages at the alternator to be sure you have available power for the alternator to work?

what is the voltage at the battery with the engine running?

https://www.2carpros.com/articles/how-to-check-a-car-alternator

I attached a diagram for you to view. the TIPM supplies power to the PCM for the field controls for the alternator. make sure there is battery voltage to the two terminals listed with the key on engine off.

Roy

Roy
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Jan 2, 2019 at 8:53 AM
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KAYKONES45
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You were very helpful. I did check the voltage and it came in at 9 and a weak 10 but kept dropping it would not hold the charge at all.
Jan 2, 2019 at 10:54 AM
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ASEMASTER6371
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did you charge the battery? the alternator will not work below 12 volts.

Roy
Jan 2, 2019 at 4:33 PM