was changing the front passenger side ,headlight,,when accidently the hose or tube came off from im guessing the wiper washer hose...so when i tried the windshield washer..water was coming off the hose..cant seen to find wher to connect back to the headlight ,,also from this being disconnected,,would this cause the service light to come on...in the meantime i just put a screw at the end of the hose , so it would not leak windshile washer fluid...

 

That will not cause the Service light. The service light is an oil change reminder light.
The hose usually attaches by where the blade snaps on. The nipple will snap off usually.

 

there is already a hose there at the headlight....as mentioned before ,,for now just put screw at the end and zipped tied it..that wont wreck any thing will it?
i figure next time i go to volvo,,maybe they can reconnect the tube

 

That should not harm anything at all.