The neutral or park switch signal is wrong. The usual complaint is a car that will not crank, or that cranks in gear when it should not.
P0850 — also written PO85O, P 0850, 0850 — is the OBD-II code for park/neutral switch input circuit. Same code, same fix: this page covers every spelling of it.
P0850 is a transmission fault code, typically costing £90–£420 to put right in a UK garage.
What causes P0850?
- Failed neutral safety or inhibitor switch
- Misadjusted selector linkage
- Corroded connector at the gearbox
- Worn selector cable
How P0850 is fixed
- Adjust or replace the inhibitor switch
- Set the selector cable correctly
- Repair the connector
P0850 repair cost in the UK
Most P0850 repairs land between £90–£420 including parts and labour. The spread is wide because the cheap fix (a sensor, a hose, a leak) and the expensive fix (a major component) throw the same code — which is why a proper diagnosis before parts are bought saves the most money.
Can you drive with P0850?
Yes, though it may refuse to start until the selector is jiggled.
Urgency: medium.