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 a part of the car that helps move the transmission fluid isn't getting enough power. It's like when a toy car's battery is running low and it can't drive as fast.
The P0B01 code indicates that the current in the 'U' phase of the electric or auxiliary transmission fluid pump motor is below the expected level.
The electric or auxiliary transmission fluid pump motor is responsible for circulating transmission fluid. The motor has multiple phases, and the 'U' phase is one of them. This code is triggered when the current in the 'U' phase is detected to be lower than the manufacturer's specified range, which can affect the performance of the transmission fluid pump.
• Transmission overheating
• Poor transmission performance
• Warning light on the dashboard
• Faulty transmission fluid pump motor
• Wiring issues or poor connections
• Defective motor control module
Transmission Fluid: A liquid used to lubricate and cool the components of a vehicle's transmission.
OBD-II: On-Board Diagnostics, a standardized system for self-diagnostics and reporting in vehicles.
• Check for any stored codes and freeze frame data.
• Inspect the wiring and connectors related to the transmission fluid pump motor.
• Test the transmission fluid pump motor for proper operation.
• Repair or replace damaged wiring or connectors.
• Replace the transmission fluid pump motor if faulty.
• Replace or reprogram the motor control module if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$200 - $800
Moderate
• Chevrolet Volt
• Toyota Prius
• Ford Fusion Hybrid
• Regular maintenance of the transmission system
• Ensure proper fluid levels
• Check electrical connections periodically
Sensor Issue
• Do not ignore the warning light; have the vehicle checked promptly.
• Avoid driving the vehicle aggressively until the issue is resolved.
Check with the vehicle manufacturer for warranty coverage on the transmission system.
This code has been reported in hybrid and electric vehicles with auxiliary electric pumps.
Moderate – It should be addressed soon to prevent potential transmission damage.
Driving with a malfunctioning transmission fluid pump can lead to transmission damage and safety issues.
• Vehicle at operating temperature
• Transmission in drive mode
The electric transmission fluid pump is typically located near the transmission assembly.
Q: Can I drive with a P0B01 code?
A: It's not recommended to drive for extended periods with this code, as it can lead to transmission damage.
Q: How can I reset the P0B01 code?
A: After fixing the issue, you can use an OBD-II scanner to clear the code. If the problem persists, the code will return.
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