WestCoastDan
JK Enthusiast
No leave them, you only need to clean and inspect the old ones. When 12v's leave the Positive Post on the Battery it has to be able to return to the Negative Post on the Battery for the circuits to work.
TECHNICALLY... electrons travel FROM Negative TO Positive.
My Charger had a plastic mechanism in the shifter assembly that was apparently prone to breaking.
It was a pink plastic gizmo that could be seen when the cover was removed.
This device (or one similar) was breaking in multiple models and it would cause a no-start because the trans wasn't sending the PARK signal.
Get a meter on that park switch.