Volvo: 1988 volvo 240 brake & back up lights, reverse light switch, brake light switch

Question
Hi Ray; I hope you can help me! My right rear brake light does not work. the left(drivers)works fine. I have checked all bulbs, wiring, fuses, but no right rear brake light. The tail lights work fine.Also both back up lights do not work when put in reverse. As above, I have checked the fuses, bulbs, and the wiring that I can reach with a trouble light. Any suggestions Ray.

Answer
Russell,
Ok with the test light where does the power stop? No power to the rear? That would be a reverse light switch. If an auto trans is under the shifter cover, on the trans if a stick shift. Did you test the brake light switch? Power both side pedal depressed? If yes look at the bulb out warning relay. Large relay just under the head light switch red ot black. There is a power into the relay and three going out one to each light. See how far you can trace the power flow. If no power at the rear start at the front, ie brake light switch bulb out relay reverse light switch. Bulbs and sockets good, power to the light connectors, the circuit card in the taillights going bad.