Use a test light or voltmeter to test for 12 volts on the terminals in the socket. One will have voltage when the brake lights are turned on, and a different one will have 12 volts when the tail lights are turned on. If that second voltage is missing, the first suspect would be a corroded terminal in the socket. Next would be a cut wire.
Friday, September 26th, 2014 AT 3:57 PM