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Did you install a new voltage regulator? Is the belt tight? Maybe the "computer brain" is weakening.


If you have installed a new alternator and new battery, check the harness/wiring that plugs into the alternator, it may be corroded/bad connection causing your battery to not be recharged at idle speed; voltage should stay between 12-14.5v range and steady (some momentary drop may occur after turning hi beam lights, etc but it should return to proper voltage after a few seconds), as for the regulator, on most cases it is inside the new alternator so no further adjusting may be required; also, make sure you get the right alternator for your focus-there's like 3 types, the wrong one will cause your dashboard alternator lamp to be lit at all times-replace with right one or higher output if got power windows,seats,etc.Good luck! Buena Suerte!

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โˆ™ 2007-09-18 22:34:25
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Q: Why is voltage dropping slowly after installing a new alternator and a new battery on a 2002 Ford Focus SE?
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