Hello I will help you with your question,
Take a 12 volt test light and check for voltatge at the connector to the lamp housing on the white/tan wire at the lamp connector. Does the center lamp work?
Let me know if you have power at the white/tan wire with the brake pedal depressed and if the center lamp works.
OK then you are going to have to check for power at the brake switch, The pink/black wire should be hot at all times and the white/tan should show power when you depress the pedal.
How is your 4th?
OK then there must be an open between the switch and the back so you are going to have to do some hunting.
Check connector C203 as it is after the split to the ABS controller and before the split to the right brake light and the center light. C203 is in the left kick panel and is shown in the diagram below. Look for corrosion and check for power to the white/tan wire ther with the pedal depressed.
let me know what you find
OK I will be here so let me know what I can do to help,
The split to the center brake light is just beyond the connector C203 so I think you will find the problem near there. just follow the white/tan wire til you lose power and you will find it
Let me know what I can do to help