Are you using googleSearch component or googleSearch_cse component?
I believe you are using the googleSearch component which uses the old google search API. This might be the reason why it stopped working because google might have stopped supporting the old API.
The new component and accompany module is here:
component: googleSearch_cse component
module: googleSearch module
Just like the older version, please install the component first, make sure it's working first. Then install the module. The module requires the component.
For the new version, everything is set in your google adsense account. You might want to try it out on your local server first and see if it works.