P0850Park/Neutral Switch Input Circuit
- Generic OBD-II code · Powertrain
- Matters for the ITP
- How the car detects it
- The park/neutral input tells the engine control module whether the automatic is in P or N, or a manual gearbox in neutral. It releases the starter, prepares idle control for the load of an engaged gear and enables cruise control and other monitors. All documented makers check it for plausibility against driving state or a second source such as the gearbox module. On GM's 6T70 and Subaru the switch pulls the line to ground in P/N. P0850 is the general fault. Ford's 2023 diesels check the switch for plausibility at start-up and set the code after 1 s. On GM's 6T70, as in the Saab 9-4X, the module sees P/N while the range switch reports a gear for 0.2 s above 10 km/h and 75 Nm, type C without MIL; it then uses the range switch for start release.
- What you may notice
- Engine does not crank in P or N
- Engine cranks in a drive range (safety risk)
- Rough or wrong idle
- Cruise control not working
- Likely causes
- LikelyRange or inhibitor switch faulty or misadjusted
- PossibleSelector cable misadjusted or stretched
- PossibleWiring or connector between switch, gearbox module and engine module
- RareModule input or software
- Inspection (ITP)
- Can matter for the ITP: it concerns the emissions system.
- Repair
- Medium · Usually a job for a workshop.Typical cost: €80 – €450
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.