Whenever I put any type of load on the electrical system such as, A/C, cooling fans, turn signals, windows, sunroof, etc. the interior lights dim and then return to normal brightness after a fraction of a second. The interesting part is that this is only when the car is running. If I just turn the key to the accessory notch without turning on the engine the lights do not dim.

Took the car to Autozone and the alternator/battery tested fine.

Any thoughts for me? I'm considering ELD.