Motorcycle Questions? Ask a Mechanic.
Hi and thank you for your question.
For starters, I would suggest checking to see if you are getting voltage to the brake light socket when the key is on and you hit the brakes. Be sure to check the front and rear brakes in case it is just one switch creating the problem. If you have power to the socket, replace the bulb and see if your red light goes out on your dash.
If you need further assistance, please provide the make, model and year of your bike.
Thank you for the additional information. Go ahead and test for voltage at the brake light socket and let me know what the results are if you need additional help.