Since you don't know which end is defective, you might take the remote to about any store that sells and services consumer gear; they will have a primitive sensor that can detect if the remote is putting out some infrared but the common type of detector cannot tell you if the coding is correct or not. If you find though that the remote is putting out anything at all, it is probably working properly. Unfortunately that will mean that the receiving end is bad and that will be more costly to have repaired. A handy device can be had for $10 US here: http://www.ersweb.com/Infratector.htm
Answers & Comments
Since you don't know which end is defective, you might take the remote to about any store that sells and services consumer gear; they will have a primitive sensor that can detect if the remote is putting out some infrared but the common type of detector cannot tell you if the coding is correct or not.
If you find though that the remote is putting out anything at all, it is probably working properly.
Unfortunately that will mean that the receiving end is bad and that will be more costly to have repaired.
A handy device can be had for $10 US here:
http://www.ersweb.com/Infratector.htm