2008 Outback All Exterior Lights Intermittenly flickering/Dimming

[jbancala]

The Outback has 250,000 miles on it. An alternator was installed by a Subaru dealer and since then I noticed a problem. Whether a coincidence or a new problem, exterior lights are now flickering. My alternator is putting out 14.4 volts and the battery reads 12.7 volts fully charged. The problem is approximately every three seconds, all the exterior lights will flicker. As the flickering is occuring, the volts put out by the alternator will go from14.4 to 13.9.

There is no problem starting the car, as the battery is being fully charged by the alternator. The flickering is consistently occurring approximately every three seconds. When the car is first started, when cold, it may take 10 seconds to start the flashing. This has me stumped. I would appreciate any thoughts on my issue.

Thanks, John

 

[Ecmbuster]

Maybe it's an incorrect or damaged alternator that should be PCM controlled. Have the dealer test it again and also have them measure any AC ripple that it produces when the alternator is operating.
I will assume without the engine running, there is no "light flicker" providing the lights are stock (OEM) and expect the flicker with non stock LED lights.