Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means the car's computer thinks the car should be in park, but it's not. It's like when you tell your toy car to stop, but it keeps moving.
The powertrain control module (PCM) in a hybrid or electric vehicle detects that the transmission is not in the park position when it should be, according to the driver's command.
The P1B31 code is triggered when the Hybrid/EV Powertrain Control Module identifies a discrepancy between the commanded park position and the actual position of the transmission. This can indicate a malfunction in the transmission control system or a failure in the park position sensor.
• Vehicle not shifting into park
• Warning light on dashboard
• Transmission not responding to commands
• Faulty park position sensor
• Transmission control module malfunction
• Wiring issues or poor connections
PCM: Powertrain Control Module
OBD-II: On-Board Diagnostics II
Transmission: The system in a vehicle that transmits power from the engine to the wheels
• Check for additional trouble codes
• Inspect park position sensor and wiring
• Test the transmission control module
• Replace faulty park position sensor
• Repair or replace damaged wiring
• Reprogram or replace transmission control module
• OBD-II scanner
• Multimeter
• Diagnostic software
$200 - $800
Moderate
• Chevrolet Volt
• Toyota Prius
• Nissan Leaf
• Regular maintenance of transmission system
• Check and repair wiring issues promptly
• Ensure software updates are applied
Transmission Control Issue
• Do not ignore warning lights on the dashboard
• Have the vehicle inspected by a professional
• Avoid driving the vehicle if it does not shift properly
Check with the vehicle manufacturer for warranty coverage on the transmission system.
This code has been reported in hybrid and electric vehicles, particularly in models with complex transmission systems.
High – This issue can prevent the vehicle from being safely parked, leading to potential safety hazards.
Driving with a malfunctioning transmission can be dangerous. Ensure repairs are made promptly to avoid accidents.
• Vehicle in park position
• Driver commands park mode
The park position sensor is typically located within the transmission assembly.
Q: Can I drive my car with a P1B31 code?
A: It's not recommended to drive the vehicle as it may not shift into park properly, which can be dangerous.
Q: How can I reset the P1B31 code?
A: After repairs, use an OBD-II scanner to clear the code. However, ensure the issue is fixed to prevent the code from returning.
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