Few weeks ago while driving my battery light came on, I figured it was the alternator, so I replaced it. That lasted about 2 weeks yesterday my battery light came on again, so i pulled the battery took it to autozone they tested said it was bad so i picked up another. Now today the battery light is coming on again. It cranks over fine voltage gauge reads 14 but when I give it gas it will drop to 8-9 and the battery light will come on. At idle it will stay at 14 and randomly drop to 8-9. Horn, lights, radio, and AC works fine so i'm starting to think maybe it's the the instrument panel.

 

I would go through all of the grounds on the engine and in the engine compartment. You will have a major ground on the back of each of the cylinder heads.

Also, make sure that all of the positive wire connections are clean and tight.