Weird Gauge Pulsation.

[IRQVET]

So today when the engine was running, the A/C was blowing, but I was stopped at a light; when the lights on the dash began pulsating on and off.

I glanced at the juice meter and it was dead center with no movement, and the alternator and battery are new. (Not remanufactured)

Any ideas????

I was thinking voltage regulator, but a friend of mine told me the newer Tahoe's don't have an external voltage regulator and they are now self contained within the alternator.

 

[retorq]

Don't all GM alternators have internal voltage regulators??

 

[IRQVET]

I have no clue. Thats why I was wondering if anyone could point me in the right direction.