If your vehicle is showing car won't start in park but starts in neutral, here are the most likely causes and the parts you'll need to fix each one.
This switch prevents the car from starting while in gear. Over time, the electrical contacts specifically for the 'Park' position can wear out or corrode, while the 'Neutral' contacts remain functional.
The cable connecting your shifter to the transmission may be stretched or improperly adjusted. When you select Park, the transmission lever doesn't travel far enough to trigger the safety switch, but Neutral aligns perfectly.
Worn plastic or rubber bushings in the shifter assembly create excessive play or 'slop'. This physical looseness prevents the shifter from pushing the transmission fully into the Park detent.
In modern vehicles with electronic shifters, the TCM interprets the gear position. A rare electronic fault or internal range sensor failure can cause it to fail to recognize the Park signal.