theresa, this is what the manual has to say :

Symptom

Both tail lamps do not come on (Headlamps are normal).

1. TAIL fuse

2. TAIL relay (USA only)

3. Headlamp dimmer switch assy

4. Daytime running light relay (USA only)

5. Wire harness

The tail lamp relay is relay number B, 2md from the left in the RH junction box

15. TAILLAMP RELAY

(a) Measure the resistance according to the value(s) in the

table below.

Standard:

Tester connection Condition Specified resistance

3 – 5 Always 10 kW or higher

3 – 5

Apply B+ between terminals 1 and 2 Below 1 W

If that is not the cause, I would check the headlight dimmer switch (sounds more like it because of your dash light being out as well

Hope this helps, good luck.