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Can't get the Fiesta to stop overcharging

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SF Bay Area
#1
I can't get my Fiesta to stop charging at 15v. I've replaced the alternator & battery but I'm still getting 15v. Any ideas? No error codes so far but I'm only driving it a few minutes at a time to get datalogs. I don't want to cook the electrical system running it at 15v for too long.

Backstory: I'm pretty sure this happened when I was replacing my a/c compressor. When I was reinstalling one of the hoses, the metal hose shorted out on the alternator which blew my main 200a fuse (integrated into the positive battery terminal). I replaced the main fuse and I'm pretty sure that's when it started charging at 15v.
 


M-Sport fan

9000 Post Club
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#2
Do you know what the system was charging at before the short/fuse replacement?

From what I can gather, it is 'normal' for our system to charge at up to 14.7 volts, which I am grateful for since my Odyssey AGM battery requires at least 14.4 volts in order to charge properly.
 


OP
bflan2001
Messages
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Location
SF Bay Area
Thread Starter #3
I don’t, unfortunately. It is possible that it’s been this way for a long time. I’ve only put a couple hundred miles on it since I’ve owned it and I only noticed the issue when I turned the voltage readout on the AP gauges.
 




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