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  • 1965 - 1973 Classic Mustangs -General/Talk-

Alternator Light Flickers, Stops When Headlights Are On

  • Thread starter Thread starter Braden65
  • Start date Start date Feb 15, 2015
B

Braden65

Member
Jan 14, 2014
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Feb 15, 2015
#1
  • Feb 15, 2015
  • #1
My 65 289 alternator light flickers on occasion. This doesn't happen often but when it does its usually only noticeable at night because of how dimly it flashes. I pull the headlight switch whether it be parking lights or headlights the light stays completely off. I measured the volts at the battery while this going on and its showing ~14.4 headlights on or off doesn't seem to affect battery voltage. Ideas on where to go from here? Voltage regulator is fairly new but you never know
 

tos

Founding Member
Apr 27, 2001
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Cincinnati Ohio
Feb 16, 2015
#2
  • Feb 16, 2015
  • #2
I'd check for loose wires, loose terminals, loose belt, but if you are getting that much voltage to your battery then I wouldn't worry too much unless its just an annoyance for you. If you have one of those Chinese made voltage regulators then I would suspect that the signal from it would be off a little. Substandard electronic circuitry = poorly calibrated voltage signals. I had one of those and although it worked properly, it smelled like burning wires and got so hot you could barely touch it. I'm sure it wouldn't have lasted long so I canned that one and put the original back on.
 
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Braden65

Member
Jan 14, 2014
70
0
7
Feb 17, 2015
#3
  • Feb 17, 2015
  • #3
tos said:
I'd check for loose wires, loose terminals, loose belt, but if you are getting that much voltage to your battery then I wouldn't worry too much unless its just an annoyance for you. If you have one of those Chinese made voltage regulators then I would suspect that the signal from it would be off a little. Substandard electronic circuitry = poorly calibrated voltage signals. I had one of those and although it worked properly, it smelled like burning wires and got so hot you could barely touch it. I'm sure it wouldn't have lasted long so I canned that one and put the original back on.
Click to expand...

Might try changing the volt regulator,can't hurt thanks
 
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Braden65

Member
Jan 14, 2014
70
0
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Mar 20, 2015
#4
  • Mar 20, 2015
  • #4
After taking the voltage regulator off to check it, putting it back on the ALT light stayed on brightly. Bought a new voltage regulator, that fixed it.
 
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