Voltage jjumping 1992 ford f250
My truck is running fine but the voltage
keeps bouncing. My lights will get dim
then bright. Open for advice
Sounds as if your have a loose connection on a wire. I would look over as much as the wiring as you can to see if you can find anything.
After you have checked the wiring, grab your voltmeter and check the output voltage from the alternator, voltage should be 13.2 to 14.8 volts, if voltage is not stable then replace the voltage regulator, and if the brushes are worn best to replace them also, then have your battery load tested, a weak battery can cause this also.
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