P0851
Park/Neutral Switch Input Circuit Low
Generic code
Transmission System
High severity
Hard repair
Free on OBD DashX
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What P0851 means
- The fault code P0851 indicates that there is an issue with the input circuit for the park/neutral switch, causing it to become low. This can affect the transmission's ability to switch gears properly and may cause issues with starting the vehicle.
Possible symptoms
- Difficulty starting the vehicle
- Inability to shift gears or incorrect shifting
- Illuminated check engine light
- Transmission slipping or delayed engagement
Possible causes
- Defective park/neutral switch
- Corroded or damaged wiring in the input circuit
- Loose or disconnected electrical connections
- Failed transmission control module (TCM)
Related parts
- Neutral Switch: The neutral safety switch is a safety feature in automobiles with automatic transmissions. It prevents the car from starting if it is in gear. Problems with this switch will cause difficulty in shifting gears from neutral position
Possible solutions
- Replace the park/neutral switch
- Check and repair any damaged or corroded wiring in the input circuit
- Ensure all electrical connections are properly connected and secure
- Replace the transmission control module (TCM) if necessary
Free on OBD DashX
P0851 on OBD DashX
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