Ubuntu :: Scp From Shell Script Using Cron

I have a script that I would like to run using 'cron'. I want to use 'scp' to transfer files from one machine to another. I have set up the SSH keys on both machines. When I run the script from bash terminal, it works flawlessly. But when I schedule a 'cron' job to run the same script, 'scp' does not transfer the files.

'Return value' is 0 when the script is run from bash directly. But when it runs from 'cron', the 'Return value' is 1. That means, surely, that 'scp' is throwing an error. I don't know which error is being encountered. Could anybody let me know how to make it work?