Could a loose battery terminal keep the shifter button from working?I

Putting your foot on the brake should activate the shifter interlock to release the shift button. If you are hearing the click noise and the shifter lever does not release, then there is likely a concern with the shift mechanism itself. The signal seems to be getting there, but the release is not happening. I don't know of a loose battery terminal being able to cause this. www.repairpal.com/repair-shops