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Old 04-03-2013
redbaron's Avatar
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Join Date: Apr 2011
Location: London, ON
Posts: 69
Alternator over voltage

A couple of days ago while driving my truck I noticed the battery warning light come on for a few seconds before going out again. When I made it home I checked the battery with a multimeter and got a reading of nearly 15v. When I started the truck I measured nearly 17v with the alternator running. I checked the connections on the battery and the alternator for corrosion, etc. and everything looked ok. The voltage on the battery dropped back down to just under 13v overnight.

I was able to order a new voltage regulator for the alternator, but before replacing it I checked the voltages again and they appear normal today - 12v on the battery and 14v with alternator running.

Is it possible that I have an intermittent failure in the voltage regulator, or is there something else I should check before replacing it?

Thanks for the help!
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Old 04-03-2013
06RangerXLT's Avatar
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sounds intermittent. id swap the regulator to be safe and save you a battery.
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Old 04-04-2013
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Join Date: Apr 2010
Location: Knoxville, TN
Posts: 631
Go ahead and replace before you fry all your modules. One guys did the same thing on his 99 and he had to replace every electronic module that over stressed due to the higher voltage.
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Old 04-06-2013
ranger4.0's Avatar
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i would absolutely replace the regulator
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Old 04-07-2013
redbaron's Avatar
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Join Date: Apr 2011
Location: London, ON
Posts: 69
Regulator has been replaced. Voltages look good now.
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