my lights didn't go out.
Bad fuse
remove the instrument panel cover..remove the radio...the black cover of the radio will need to be removed...you'll need a star screw set...once you have the screws undone...be care..the buttons might fly off...inside there should be really tiny bulbs...its either a 73,73, or smaller than a 26...just match em up at an auto store...then they should work. The instrument panel lights are grounded to the radio, so be sure there is a good connection from your radio to ground.
check the fuse
you need a new ignition tumbler.
It is not difficult. First you have to remove the 12vot cigarette lighter plastic and then remove the radio. 4 screws for the radio. Then you have to remove the panel that goes from the radio up to the instrument cluster. This panel has 4 screws. 2 of them are on top of the instrument cluster (visible) and the other two should be visible after removal of radio.
Are there tail lights? If not, then the light switch itself might be bad. If the tail lights/running lights are working, and only the dash is affected, did you put in an aftermarket radio? It gets kind of complicated after that.
It could be a blown fuse. Do the tail lights work? On many cars, this one I think, the tail lights and instrument illumination lights are on the same circuit. The under-dash fuse panel likely has the fuse in it. (If not, a few cars have a secondary fuse panel under the hood.) There should be a fuse panel cover with the fuse identification on it. If not you will need help locating the correct fuse. Or get help from a parts store and use a test light to check all the fuses to find any blown ones. If the fuse is blown, and a replacement blows you will need to find a short on the circuit. If someone has installed a after-market radio check there first. They may have mistaken the illumination wire for a radio ground wire and connected radio ground to the illumination circuit. This is a fairly common problem with radios installed by do-it-yourself or inexperienced installer.
bad wireing or your insterment panel dimmer switch is bad
it is located behind instrument panel on top of radio.
I had a similar problem with a Pontiac some years back. It was a bad dashboard ground. It may not be it, but I would start there.
i believe there is a bulletin from Toyota on this problem. on a 2006 you should just bring it to the dealer anyway!
broken circit in your light switch