The Qualified Plug-in Electric Drive Motor Vehicle Credit is a non-refundable credit. A non-refundable credit can reduce your tax liability to 0 (zero); however, it cannot result in a refund. So, if you qualify for a $350 credit and your tax liability is $200, you will only receive a $200 credit on your return. If your tax liability is zero, you will not receive the credit at all, even though you are otherwise eligible for it.
Note that any link in the information above is updated each year automatically and will take you to the most recent version of the document at the time it is accessed.