The battery light on and the A/C does not work, is it the serpentine belt, or alternator?

BENJAMMINB6

MEMBER
2018 HYUNDAI SANTA FE
4 CYL
2WD
AUTOMATIC
110,000 MILES

Battery light came on while driving, and shortly after all indicator lights began flashing at once. Power steering seemed to go away; A/C stopped blowing cold. Immediately pulled into a repair shop. They did an oil change, new brake pads, and put in a new battery. That was yesterday. All indicator lights are off again, but battery light is still on, and A/C still does not blow cold. Is it more likely to be that I need a new alternator? Or possibly just the serpentine belt needs to be replaced to crank the A/C and get battery voltage right? How do I know if I only need the belt replaced, or if I need the whole alternator replaced? Car seems to be running fine, it just has the battery light on, and the A/C doesn't work.

1 Reply

JACOBANDNICKOLAS

MECHANIC
109,758 POSTS

Hi,

The idea that the battery light is on likely indicates the alternator isn't charging. If the belt is attached and not loose, that isn't the likely cause. Also, a loose belt will usually make noise. (Squealing)

If the alternator isn't charging, the A/C may be disabled to prevent battery drain, so we need to check the alternator. All you will need to check it is either a voltmeter or multimeter. It's very simple to do.

Follow the directions in this link and let me know the results:

https://www.2carpros.com/articles/how-to-check-a-car-alternator

Try this and let me know the results. If you are uncomfortable performing the test, most auto parts stores will do it for you free of charge.

Let me know.

Joe