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 a problem with the electric pump that helps move the transmission fluid. It's like if a part of a machine that helps it work smoothly isn't doing its job right.
The P0B03 code indicates an issue with the current in the Phase V circuit of the electric or auxiliary transmission fluid pump motor.
The P0B03 diagnostic trouble code is triggered when the vehicle's powertrain control module (PCM) detects an abnormal current reading from the Phase V circuit of the electric or auxiliary transmission fluid pump motor. This pump is responsible for maintaining the necessary pressure in the transmission by circulating the transmission fluid, which is crucial for proper gear operation and cooling.
• Illuminated check engine light
• Transmission overheating
• Poor transmission performance
• Faulty electric transmission fluid pump motor
• Damaged or corroded wiring or connectors in the pump circuit
• Defective powertrain control module (PCM)
PCM: Powertrain Control Module
OBD-II: On-Board Diagnostics, Second Generation
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors of the transmission fluid pump motor.
• Test the electric transmission fluid pump motor for proper operation.
• Replace the faulty electric transmission fluid pump motor.
• Repair or replace damaged wiring or connectors.
• Reprogram or replace the PCM if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$200 - $800
Moderate
• Toyota Prius
• Chevrolet Volt
• Nissan Leaf
• Regularly check and maintain transmission fluid levels.
• Inspect electrical connections for corrosion.
• Follow the manufacturer's maintenance schedule.
Sensor Issue
• Do not ignore the check engine light; get it checked promptly.
• Avoid driving the vehicle if the transmission is not performing well.
• Consult with a professional mechanic for accurate diagnosis.
Transmission components may be covered under the powertrain warranty. Check with your vehicle manufacturer.
The P0B03 code has been more commonly reported in hybrid and electric vehicles due to their reliance on electric pumps for transmission fluid circulation.
Moderate – Addressing this issue promptly can prevent further transmission damage.
Driving with a faulty transmission fluid pump can lead to transmission failure, which may cause safety hazards.
• Vehicle engine running
• Transmission at normal operating temperature
The electric transmission fluid pump is typically located near or within the transmission assembly.
Q: Can I drive with a P0B03 code?
A: It's not recommended to drive with this code, as it can lead to transmission damage.
Q: How do I reset the P0B03 code?
A: After repairs, use an OBD-II scanner to clear the code from the PCM.
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