I am stuck on nomenclature really.

My friend converted his taillights from using two bulbs to using one bulb. As a result, his turning signals no longer 'click' due to lack of current. Now, I know there exists relays that simply click every 1/2 second or whatever without needing any current to make them do so, but what are they called and where can he find them? The other option was to find a relay whose current for 'clicking' was about 2/3 to 3/4 of his original. Do they exist? How might one go about figuring out what current your current one is designed for?

I have never run into this problem yet, so any help is greatly appreciated. If it's of any consequence, his car is a '90 Beretta.