Pulsating Dash Lights

[chief]

Ok, let us get the nasties out of the way. This thread concerns a potential problem with the alternator. My dash lights are pulsating. Has anyone had the same happen to them? If so, did you change out the alternator? Or, if something else, what did you do?

 

[aussie320]

I doubt if this problem would be caused by the alternator. I would suspect a loose earth in the instrument cluster lighting circuit. Does the problem remain when the instrument light dimmer potentiometer is changed to a different position?

 

[Kirby]

Does the pulsing get faster with higher RPM? If yes, it could be one bad diode (aka rectifier) in the alternator. If no, then the voltage regulator is suspect.