Start by checking the "Possible Causes" listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector's pins.
There is a Factory Service Bulletin for the following Subaru models:
2005-2008 Subaru Legacy
2005-2008 Subaru Outback
2005-2008 Subaru Impreza
2005-2008 Subaru Forester
Subaru Factory Service Bulletin OBDII Code P0851
The cost to diagnose the P0851 Subaru code is 1.0 hour of labor. The auto repair's diagnosis time and labor rates vary by location, vehicle's make and model, and even your engine type. Most auto repair shops charge between $75 and $150 per hour.
The engine control computer detects that the transmission is in the neutral state based on the signal from the Neutral Safety Switch (for Transmission M/T) or the neutral start switch assembly (for Transmission A/T).
Manual Transmission: The P0851 sets when shifting the gear position while driving the vehicle, the neutral position switch is left "Low".
Automatic Transmission: The P0851 sets when the range selector is in N or P range, the neutral switch is in P or N range and the range information from the transmission control computer indicates a position other than P or N. Also, when the range selector is neither in N nor P range, the neutral switch is in P or N range and the range information from the transmission control computer indicates a position other than P or N range
Need more information on how to fix the P0851 Subaru code? Get Access to Factory Service Manuals
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