2006 Sonata brake lights don't work except rear deck light.

The rear brake lamp is a whole module. Get the whole unit for left and right no after market one the pins are not always correct

I've worked on these the first drove me crazy. its the turn signal switch every thing runs thru these. head lights, turn signal, brakes. except the third brake light. it runs directly from the brake switch. go figuare

could be the light itself,the red brake wire that comes off the rear brake lights that feeds this stop light,sometimes things get shoved against this wire and its cut,or if it splits off in the frame,it could also be broken here too

the carpet cover comes off the rear deck in the back windo then you will find the screws that hold it down

replace the bulbs

Either all the brake lamp bulbs are burned out... OR, it's the brake switch.. OR, a fuse.

There was recall for the 2006 and 2007 Hyundai Sonata Brake Light Switch assembly. www.promanuals.net

Hi welcome to fixya.com
Try putting on your flashers,and see if they come on.
Sounds like a loose groung wire usually green.They need to contact bare metal.lots of times they just need retighting.

the bulbs are a dual philament eventhough the tail lights work the brake light part of the bulb is burnt out

This is how i did it on my 2006 Sonata

1.) unplug the connector in the trunk (its a small white plug running up to the third light, there should be a small clip you squeeze).

2.) remove the 2 gold-colored screws from inside the trunk. They can be seen from the trunk. 1 is thru the larger square opening where the wire connects to the 3rd brake light. The 2nd is on the right side thru a small (screwdriver width) hole covered by a piece of foam tape stuff I had to punch me screwdriver through the foam to get to it.

3.) after removing the 2 screws, go inside the cabin and the brake light housing pops up.

4.) disconnect the bulb from the housing while inside the cabin (I had to do this with me two forefingers since the housing only pops up and inch or two).

5.) in the trunk remove the wire and bulb. (it's about 5 inches long. the wire from the connector to the bulb socket)

6.) reverse steps to install.

It is a pain and reqiuires a bit of time only because there isn't a lot of room to move around, but it beats taking it to the dealershio!