My brake light and battery dash lights came on when I got home. The next day drove 3 miles parked no lights on . But on my way bak. about 1/12 miles they came back on. Next trip they came on when first started the car stayed on for about 9 miles once I got on the. Hwy they went off stayed off till I hit town about 30 miles. Stayed on till I parked the car. When I left to return home lights still on. While drivinng. n all dash lights came on then went real dim to no lights transmission and brakes felt like they were losing power .parked the car the next morning it stared right up but break and battery light still on moved it a couple blocks to my sons house . When the lights went off on the hey. Then heater fan would kick up when lights are on heater fan runs slower. Any ideas on what it could be ?
Your alternator is in its last death throes, and is likely to give out totally in the next day or so.
At that point, your vehicle will essentially be “dead in the water”.
I would suggest that you get the vehicle to a mechanic now, before you also have to pay for a tow.
(Actually, if your Santa Fe has AWD it can’t be towed, so when that ailing alternator dies, you will need to get a flatbed car carrier in order to transport it to a mechanic.)
As an added inducement to take the car to your mechanic NOW, I will add that the longer you delay, the greater the probability that you will also need to replace the battery–in addition to the alternator.