Rear brake light problem

The tail light housing bulb holders are notorious for not making good contact to the tail light housing. Remove the housing, and disconnect the electrical connector. Label each bulb holder prior to removal, with a marker pen. 1, 2, 3, upper, middle, lower, etc. Remove each bulb holder, by turning counter clockwise 1/2 turn, and withdraw holder. Inspect each contact. You can bend the contacts outward a tiny bit, just flex it a tiny bit, and check with an ohmmeter for contact. Also inspect the bulb holders for melting from bulb heat, so much so that the plastic holder, which contains the bulb contacts, no longer make proper contact to the bulb. Also check the bulbs with an ohmmeter to verify that the bulbs are good. When reinstalling the bulb holders, check that the little flanges on the holders are properly inserted into the tail light housing. Reconnect electrical connector, and reinstall housing into vehicle. On a further note, with the electrical connector disconnected from the housing, you can check for voltages from the connector pins to ground, using a voltmeter. Turn ignition switch to run position, turn on headlight, and turn on blinker, or use stick to push brake pedal, against front of seat, and verify voltage from pins to vehicle frame (or connector ground pin). If no voltage, then check fuses, or broken wiring. My experience, however, is poor connection from bulb holders to tail light housing.