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 has detected that the electric pump that helps move transmission fluid isn't getting enough power. It's like when a toy car's battery is running low and it doesn't move as fast.
The vehicle's control module has detected a low current in the Phase V of the electric or auxiliary transmission fluid pump motor.
The P0B04 code indicates that the electric or auxiliary transmission fluid pump motor is experiencing a low current condition in its Phase V circuit. This may be due to electrical issues such as a bad connection, a faulty motor, or a problem with the control module.
• Check engine light is on
• Transmission may not shift properly
• Reduced fuel efficiency
• Faulty electric transmission fluid pump motor
• Poor electrical connections
• Faulty control module
Transmission Fluid Pump: A device that circulates transmission fluid within the transmission.
Control Module: A computer that controls various functions in the vehicle.
• Use an OBD-II scanner to confirm the code.
• Inspect the electrical connections to the transmission fluid pump motor.
• Test the transmission fluid pump motor for proper operation.
• Repair or replace faulty wiring or connections.
• Replace the electric transmission fluid pump motor if defective.
• Replace or reprogram the control module if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$200 - $600
Moderate
• Toyota Prius
• Chevrolet Volt
• Ford Fusion Hybrid
• Regular maintenance of the transmission system.
• Ensure electrical connections are secure.
• Use quality replacement parts.
Electrical Issue
• Do not ignore the check engine light.
• Have the vehicle inspected by a professional.
• Avoid heavy loads until the issue is resolved.
Check if the vehicle's powertrain or emissions warranty covers this repair.
This code has been more common in hybrid vehicles due to their reliance on electric pumps.
Moderate – It should be addressed soon to prevent transmission damage.
Driving with a malfunctioning transmission pump can lead to further damage and is not recommended.
• Vehicle at operating temperature
• Transmission in drive mode
The electric transmission fluid pump is typically located near the transmission housing.
Q: Can I drive with code P0B04?
A: It's not recommended to drive for long periods, as it can lead to further transmission issues.
Q: How is the electric transmission fluid pump different from a regular pump?
A: An electric pump is powered by the vehicle's electrical system, while a regular pump is usually driven by the engine.
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