Those trying to go through Google AdSense to generate a search box for their web site might be out of luck. According to a Google AdSense Help thread, the ability to create valid code to place on your web site, so that you can enable Google search and monetize that search on your web pages has been buggy.

Early reports came March 31st, with no answer until Friday. The first report said:

Finally, this past Friday, April 9th, Google’s AdSensePro Annie replied to the thread confirming the issue:

There is no ETA for the fix and it appears the issue is still there for many publishers.

So if you want to monetize your search pages, maybe try google.com/cse as a work around.

Forum discussion at Google AdSense Help.