Thanks for reply. I found some good information in the following link:
http://www.v8sho.com/SHO/DaytimeRunningLights-Diag.htm
It is for SOHO but everything is same as Taurus.
I recommend it to anybody who has problem with DRL.
Now I am looking for a used DRL for my taurus 1997. As sson as i install it, i let you know of the results.
Reza