I have an 07 Santa Fe. Yesterday, I drove this car to work and drove it throughout the day. No problems with starting or any power issues. After I came home late afternoon the car sat for several hours.

Last night, I went to start the car to leave the house and as I was turning the key the car just went completely dark and no power. Nothing. The door locks didn't work, no lights on the dashboard, just completely dead.

This morning, I looked at the battery and everything appeared normal. The cables on the battery were tight, no corrosion, everything looked ok. I opened the fuse box, by the battery, and popped the fuse "START" and put it back in and suddenly I got power. The car started and I had power again.

What, possibly, happened to the car? How did the car lose power? Is this an early sign of something failing?

 

Hi:
That sounds similar to a problem with my 05 Santa Fe a few months ago.
https://www.hyundaiforum.com/forum/h...steries-20415/
No solution yet, but it has happened twice. The first time I described in that thread. The second time it was very brief: reseating the negative battery post connector brought the power back. It could be a bad ground connection somewhere. Or you might have solved it. If it happens again, I'll try that Start fuse.

 

Just a follow up. The car continues to lose power randomly. The "start" fuse in the fuse box near the battery, seems to give the car power. After I lose power, I will disconnect it then reconnect it and the car has power again. I am not sure what relationship it has but seems to give the car power.

I don't know yet if this issue is battery, alternator, or something else. I will bring it in to my repair guy to look at it.

 

Possibly? at least you fixed it for now. i dont keep vehicles that old usually by the 12 year or so i start asking myself what coloure is my next vehicle going to be. lol

 

try wiggling the key in the ignition does it stall? also with the engine running tap gently on the starter rely does that stall the engine? if so you need a new one