Auto Electronics: brake light, multifunction switch, hello bill

Question
I have 1996 towncar the left brake light does not come on! The bulb has been changed,the right and center lights work properly when the brakes are applied, your help would be appreciated.     

             thks Bill

Answer
Hello Bill. Looking at the wiring diagram, I see the circuit feeds from the brake pedal switch directly to the center brake light bulb. It also feeds from the brake pedal switch to the multifunction switch and from there to the respective left and right bulbs. Since the right side is working correctly we know that the circuit to the multifunction switch is good. Inside the switch the circuit splits, with one side feeding the right side brake lamp and the other feeding the left. The problem could be anywhere between this split and the left lamp. You will need to voltage drop the circuit starting at the bulb socket. If you do not have 12 volts there, check the output of the multifunction switch next. I believe the color code is LG/O (Light Green with and Orange tracer). If you do not have 12 volts at the multifunction switch output, then the switch is bad and will need to be replaced. Hope this helps. Don.