CHMSL (Third Brake Light) Inop

My CHMSL (third or center brake light) is inop. Both tail lights/brake lights function normally. I replaced both bulbs in the CHMSL assembly and checked voltage. There is 0 V with no brake pedal applied and .12 Volts with brake pedal depressed and I get 12 V when I read directly from the main wiring harness below the seat prior to where the two wires head vertical up the back of the seat.

I tried to get a reading from the wires going into the light assembly but the assembly is sealed to the top of the vehicle even when I remove the screws.

Any ideas other than running a new set of wires?

Thanks for any help!

Put push pins thru the insulation and take a reading where the wires enter the lamp assembly.

Hi! I had the same problem. There was a connector behind the seat back that had become unplugged. I hope it’s that simple. Barry📈

Thanks for the responses…I will take a look behind the seat this weekend and try a push pin. Thanks!