I have a (previously broken) iPhone 5C that I removed the offending parts from- the screen was shattered beyond repair, and the battery was in pretty bad condition. I'm planning to buy some new parts and repair it, but I don't want to spend around $100 and find out that other parts are broken and it's non-salvageable. 

Is there a way to test the phone, maybe by making it ring or vibrate, without a battery or a screen?