what caused my brake lights to go out in '04 camry
Well since you have one working, you can rule out the brake switch under the dash and a blown fuse. That leaves burned out bulbs or a broken wire. First check your bulbs. If good, get a 12 volt pin light tester and see if you have power to the sockets. If no power, you have a broken wire or loose ground. Start inspecting the wiring harness. If it runs up through the trunk lid, check around the left hinge area really well. It tends to break in that area.
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