Toyota Repair: brake pedal activate turn signal lights, left turn signal, light bulbs

Question
1998 Toyota Tacoma - When I step on my brakes, the left turn signal lights come on solid. The front, back, and panel left signal lights all light up.  When not on the brakes, the left turn signal works just fine, no burnt out lights.  What's my problem?

Answer
Check all of the light bulbs and the sockets both front and rear, including the park and turn signal lights, the most common cause for this is that a wrong bulb is installed in one of the sockets, look for a single contact bulb being in a double contact socket and the other way around.