Chevrolet Repair Questions? Ask a Chevy Mechanic for Answers ASAP
Hello, my name is*****'m assuming you have replaced bulb. If so then this means the brown wire that goes between brake light and splice 400 is damaged somewhere. I'd start by replacing bulb again and inspecting connector condition. If good you will need to follow the brown wire to find damage. Here is a wiring diagram to help with troubleshooting, let me know if you have more questions. Thanks.
You can use a multimeter to check pin for voltage with headlights on. If meter shows voltage you know it is a connection problem, if not then you know it is a wiring problem. You should be able to visually see the damage. Let me know if you have more questions, thanks.
It is a brown wire with a white stripe, pin A of connector. Here is a connector diagram. Let me know if you have questions, thanks.