My wifes 2011 Hyundai Sonata would not start yesterday at the clinic. I purchased a new battery went there today to replace the battery. Before I started the work I tried starting the car. When I turned the key to the on position the radio came on and the dashboard lit up like normal. As soon as I turned the key to start the car the battery went completely dead. The starter did not engage and the electrical went out.
I replaced the battery. When I turned the key to the on position nothing turned on. Not the radio or any of the dashboard lights. I tried starting the car and there was not response, exactly like a dead battery. I purchased a new battery and they tested it right in front of me before giving it to me so I feel like I can rule out the battery.
I double checked that he connections were tight. I tried jiggling the shifter, pushing the brake pedal, jigging the steering wheel around, jiggling the key in the ignition. The positive battery terminal connector has a fuse, it appears to be intact. I also checked the fuse panel in the engine compartment. All of the large fuses are intact (I only looked at the 3 or 4 of the large ones that were visible from the top). I didn’t check the smaller fuses, I wasn’t sure which ones to check.
A little background;
For a couple days in a row my wife was noticing that the car was struggling to start (she didn’t mention this to me right away). I noticed that when we were driving it the head lights had a very suttle flicker. When were idling at a stoplight it appeared as if the lights were dimming and getting brighter rapidly. I noticed it from the reflection of a license plate and dismissed it as maybe just the wind causing the license plate on the car ahead of us to wobble. It was suttle and not very pronounced. Yesterday my wife went to the clinic and when she was leaving the car would not start. Someone helped her with jumper cables but she was not able to get it started. Even after letting it sit for 5 minutes before trying to start it.
My buddy thinks it’s the ignition switch itself, but that sounds quite a bit beyond my capacity.
I suspected that since the lights were fluttering/dimming that it was an alternator problem. Even if the alternator is bad wouldn’t the car still run on a fresh battery?
Can anyone suggest some other troubleshooting steps? Any ideas what the issue could be?