I need to buy a replacement key fob for a 2000 Volvo S40. I know the fob needs to be programed, does this have to be done @ the dealer?

I have a 2000 volvo s40. 90,000 miles. In May I had it @ the dealer because of check engine light being on and was told that I needed a transmission speed sensor. I had the part put on. The check engine light is now back on again and now I am being told that I need a transmission range sensor. Would...