Squeaking/whinging

Hi i have a 2001 jeep Cherokee sport 4.0 and my serpentine belt squeaks i have checked the belt and tension those seem fine but when it squeaks my voltage drops and especially when i have my ac on does this sound like a bad pulley alignment and is causing the belt to slip or maybe a bad alternator? Im not very knowing about vehicles any input would be appreciated.

You can’t determine if a serpentine belt is worn by looking at it.

Replace the serpentine belt, and the noise will probably stop.

Tester

The belt isn’t tight enough, tighten the belt. I have seen a number of Cherokees with belt squeal, it is difficult to judge the belt tension when the pulleys are so close together but the problem was always that the belt was not tight enough.