I have a light scratch on the dashboard from my finger nail. It left a very thin light colored line. How should I go about fixing this? Cleaning the area did not help.

 

scratches in vinyl are pretty much permanent-
the choices are to try a plastic polish - but my experience has been that they can make the problem bigger by spreading it.

got any pics of the damage? i wonder if you might fill it with some back to black or similar product

 

vynal repair.

 

Model shop plastic paint if it's a black dash.
Matt and semi-mat etc. are available.
For a large area you can spray but for a small scratch a little bit on your finger rubbed along the line can do the job, merge it in with a cloth.