it shows that somewhere on the tail lighting circuit there is some kind of a short circuit,one can test using a multimeter to find the probklem..
Those tail lights could be the brake lights you are seeing and that would be a faulty brake light switch or the brake light switch is out of adjustment.
Check fuses or headlight switch
I had a similar problem with my S70 and discovered the headlight switch was defective. The switch had actually begun to separate causing the contacts for the tail lights not to make contact. Try having someone observe the tail lights while you push on the headlight switch. If the tail lights begin to work, replace the headlight switch.
You may have to replace the headlight switch since your tail lights are tied into the same switch.
If the parking/tailight fuse is good - then it may be a bad headlight switch No tail lights but the bulbs are working? Please explain.
A bad brake light switch or a bad headlight switch, or the power source of the fuse has a problem or break in the wire (circuit).
If the fuse keeps blowing, there is a short somewhere. Since the dash and tail lights both go through the headlight switch, I would check the wires from the switch connection all the way to the tail lights, and the dash lights. Somewhere, a wire is crushed to ground or something like that. Make sure your switch is property connected and is a good switch! Good luck!
use a test light or a multimeter to check for power at the tail lights, check bulbs.
Because the switch is in the on position
Dash lights and tail lights are on the same fuse.
There isn't a relay involved. The power goes from the switch to the fuse and then to the lights.
Check the switch at the brake pedal .