Volvo: Taillight problem, volvo 740 gle, blown fuse

Question
Hello, i have a '86 Volvo 740 GLE and I've just encountered a problem. Yesterday i was driving and my instrument panel lights went out. It was a blown fuse so i replaced it. Now all the lights work except the tail lights. Now the brake lights work perfectly fine but when the headlights are on the running tail lights don't come on. I'm not really sure what to do... I'd would love to hear your opinion/recomendation on this issue.
Thanks,
Fil

Answer
Fillip,
If you have the mechanical and electrical knowlege grab your test light and voltage meter. Start at the fuse box and follow the power. Look for power and inspect the grounds, check the bulbs and fuses, bulb out relay. Remember the left and right lights are fused seperatly. Headlight switch, loose wires, bulb relay, fuses, bulbs all could be at fault.