Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means that the car's computer is having trouble reading whether the car is in park or neutral. It's like when you can't tell if a light switch is on or off.
The P0850 code indicates a problem with the park/neutral switch input circuit, which tells the vehicle's computer if the transmission is in park or neutral.
The park/neutral position (PNP) switch is responsible for informing the Powertrain Control Module (PCM) whether the vehicle is in park or neutral. This information is crucial for starting the engine and for certain transmission functions. A fault in this circuit can lead to improper vehicle operation.
• Engine may not start
• Transmission may not shift properly
• Check Engine Light illuminated
• Faulty park/neutral position switch
• Wiring issues or poor connections in the circuit
• Faulty PCM (Powertrain Control Module)
PCM: Powertrain Control Module, the computer that controls engine and transmission functions.
PNP Switch: Park/Neutral Position Switch, a sensor that detects the gear position.
• Check for any related codes and address those first.
• Inspect the park/neutral switch and its wiring for damage or disconnections.
• Test the switch with a multimeter to ensure proper operation.
• Replace the faulty park/neutral position switch.
• Repair or replace damaged wiring or connectors.
• Reprogram or replace the PCM if necessary.
• OBD-II scanner
• Multimeter
• Wrench set
$100 - $300
Moderate
• Ford F-150
• Honda Accord
• Chevrolet Silverado
• Regular inspection of transmission components
• Ensure proper maintenance of the vehicle's electrical system
• Avoid harsh driving conditions that may damage transmission components
Sensor Issue
• If the vehicle fails to start, try shifting to neutral and attempt to start again.
• Consult a professional mechanic if the Check Engine Light remains on.
Check with your vehicle manufacturer for specific warranty coverage on transmission components.
The P0850 code has been a common issue in vehicles with automatic transmissions, particularly as they age and components wear out.
Moderate – While the vehicle may still be operational, it can lead to starting issues and should be addressed to prevent further problems.
Ignoring this code can lead to safety issues, such as the vehicle not starting unexpectedly. It is recommended to address it promptly.
• Vehicle in park or neutral
• Engine off
The park/neutral switch is typically located on the transmission or the side of the gear selector.
Q: Can I drive with a P0850 code?
A: It's not recommended to drive with this code as it may lead to starting issues or transmission problems.
Q: How do I clear a P0850 code?
A: After repairs, use an OBD-II scanner to clear the code. If the issue is resolved, the code should not return.
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