Can ANYONE Who owns a Hyundai Sonata 2.4 sedan tell me what is holding down the rear parcel shelf just behind the passenger seats. I need to access the third brake light to replace ONE BULB. No help from dealerships except the notorious " bring the vehicle in" No such thing as " good will policies". I will be able to afford " their repair fees as a pensioner. This after finally owing my DREAM CAR... anybody please help.

SOURCE: Ford Focus brake lights staying on all the time and third brake light not working.

Great Result - glad to have helped.

SOURCE: How to Change the taillight bulb 2002 Aerio standard model

You have to unscrew one or two screws (don't remember) to remove the whole light assembly (need the hatch or trunk open to access screws). The solution is work from outside the car not inside.

SOURCE: Hyundai 2006 Sonata high mount brake light.

the rear seat does NOT have to be removed in order to replace the stoplamp and/or its bulb.
you have to get into the trunk, and there are (2) philips screws holding the stoplamp secured to the package tray. the actual process takes about 15 minutes, because to do it right you have to actually get IN the trunk.

the price they charged you sounds about right if the price of the stoplamp is included, dealerships tend to overcharge for parts.

SOURCE: 3rd brake lamp in '07 Hyundai Sonata

you need a philips screwdriver and a flashlight, and a telescoping magnet is recommended.

the best way to do this would be to empty your trunk, and lay in the trunk on your back with your legs hanging out and your flashlight pointed up at your work.
inside the trunk directly under the stoplamp you should see a connector, disconnect that and you should see a philips screw. remove the screw.
this part is a little tricky, shine the light up and to the left so that you can see the fastener that holds the bulb into the lamp. take your screwdriver, and place the tip on the flat part that sticks off of the bulb socket and press, so that you can turn it. once the socket is released, remove the bulb socket & bulb with its wire completely.
next, about 2-3 inches to the left of the rectangle where you removed the bulb & socket you should see a hole that is covered with a black foam. remove the foam from the hole, look straight up and you will see another philips screw. remove it, i recommend using a magnet to pull it from its hole after you've loosened it almost all the way, but whatever you do, do NOT do NOT drop that screw. it is almost impossible to retrieve and if you dont, it will rattle.
once you have both screws removed, get out of the trunk and go into the backseat and lift the 3rd brakelamp assembly off of the package tray; it may need a little negotiation, but be patient, it will come out.
once you have the stoplamp assembly out of the car, take the bulb socket, it should have a long flat tip at the bottom. take a pair of dikes and cut that tip completely off. replace the bulb, and install the bulb & socket into the lamp assembly, and re-install the lamp from inside the car, slowly and carefully slding it back into place. (hint, the more of the flat tip that you cut off, the easier it will slide into place).

once the lamp is back in place, hook up the connector, and re-install the screws, and you're done.

SOURCE: don't no how to replace third brake light in rear window, on hyun

possible two ways of doing this one is from inside the trunk and the other is to remove assembly from inside the vehicle.