Tail lights quit need help quick please
 

I have a 2003 350z and am having a weird concern. My tailights will not work I have checked every visible fuse with a circuit tester all seems fine. I replaced the bulb still no help. Everything else works brakes hazard turns headlight just nothing when the headlights are on. Tail lights and whatever the small 194 are in the tails do not work with switch on. Please tell me someone has seen this and found a repair.

Generic Symptom: Tail lights don't work
Symptom: Rear lamps are non-functional with the headlamp switch in the "On" position
Probable Causes: Lamps, Headlight Switch, Fuses,

Go to your last known functional mode before a change in the circuitry was made before the symptom rose.

Take a digital multi-meter & check for Voltage at the pins of the corresponding fuse at the fuse terminal distribution block. Try isolating the fault first by turning the cockpit headlight (Sw)itch to the off position & visually see if the rear tail lights illuminate(shine/turn-on). If the rear lights illuminate you have an open contact point in the headlight switch located in-side the cockpit. If the rear lamps do not turn on, perform another Voltage check at the fuses locations. I haven't had any electrical problem with my Z so I haven't had to memorize any relay locations but this should set you on the right path. Oh, some replacement bulbs have 1 or 2 contacts, assure you are using the correct one because it will leave the lamps in an (O)pen position.