squealing and voltage loss issue when heat is on.

[Trailer Ray]

So every time I turn my heat or defrost on my voltage gauge goes from about 13 down to about 10 and my belt starts squealing. Its fine if I don't have the heat on or anything but once I put it on its like its drawing more power than it should be. 96 xj auto 128,000 on it. Its got a new used alternator, new idler pulley, and new p/s pump. Idk if anyone's run into similar issues but any suggestions or help is much appreciated, thanks in advance.

[ninetysix-ex-jay]

Check the easy stuff first. Start with checking the belt tension and look for any cracks. Then, I'd have the alternator tested first at autozone. After that I would remove the belt and spin the alternator, idler, power steering, and A/C pulleys by hand. If they are hard to turn or you hear/feel a grinding noise, the bearing is shot

[Customjob]

Check the easy stuff first. Start with checking the belt tension and look for any cracks. Then, I'd have the alternator tested first at autozone. After that I would remove the belt and spin the alternator, idler, power steering, and A/C pulleys by hand. If they are hard to turn or you hear/feel a grinding noise, the bearing is shot

Agreed. I would look into the alternator, belt and a/c compressor. Im leaning toward a/c compressor. The a/c compressor comes on with the defroster to suck moister out of the air.

[wannabejeep]

happened to me too dude. I tightened my belt down good and now everything works nicely. Fixed my squealing and voltage drop.

[Trailer Ray]

thanks guys. i havent had time to look into it much but im freeing up some stuff so i should be back to working on it soon.