What is the P0851 fault codes? What is the description of the Park/Neutral Switch Input Circuit High fault? How do I fix the P0851 fault code What are the causes and symptoms of the P0851 error code?
What is the P0851 fault code? What does it signify?
A P0851 code means that the voltage signal from park/neutral switch input circuit has been set too low. This code is only applicable to vehicles equipped with an automatic transmission or all-wheel drive.
A park/neutral button is used on all-wheel drive (4WD) vehicles as well as vehicles with automatic transmissions to inform the powertrain controller module (PCM), whether the transmission is in park or neutral. The PCM may not have this information and the transmission might not function properly. The malfunction code P0851 can be issued if the PCM detects the voltage signal from park/neutral switch circuit below the minimum values.
The PCM utilizes data from the speed sensor and torque converter lock-up sonoid, as well as other sensors, to calculate engine speed, timing, fuel delivery, and other processes. This code will be stored in the event that data from these sensors indicates the transmission gear range does not meet the set parameters.
What causes the P0851 Fault code?
Below are some reasons to set fault code P0851:
- – Incorrectly or defectively adjusted transmission position sensor
- All electrical components, including damaged, rusty and open or shorted wires, connectors, and corroded wires
- Incorrectly installed sensor bolts
What are the symptoms of the P0851 Fault Code?
You may experience the following symptoms if your vehicle has the code P0851:
- – Illumination at the check engine lights
- – Inability of the 4WD system activate
- – Hardiness in changing gears or being unable to do so at all
- – Increased fuel use
How to Fix the P0851 Fault Code
Some repairs that could resolve the P0851 fault code are:
- Correction of an incorrectly set transmission location sensor
- – Replacing a defective transmission position sensor
- – Repair and replacement for damaged cables or connectors
- – Correct installation of sensor bolts
How serious is the P0851 Fault code?
The P0851 fault code directly affects the safe and smooth operation. This fault should be addressed immediately. Avoiding this fault could lead to unsafe driving conditions and even the vehicle not starting.
