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 is stuck and not working properly.
The P277C code indicates that the electric motor responsible for driving the auxiliary transmission fluid pump B has stalled, meaning it has stopped working or is unable to rotate.
The electric/auxiliary transmission fluid pump B is designed to maintain the necessary pressure and flow of transmission fluid in the system. If the motor stalls, it means that the pump is not circulating fluid as needed, which can lead to transmission issues. This code is set when the control module detects that the motor is not operating as expected.
• Transmission slipping or not engaging properly
• Warning light on the dashboard
• Unusual noises from the transmission area
• Faulty electric/auxiliary transmission fluid pump B motor
• Wiring issues such as shorts or open circuits
• Faulty control module or software issues
Transmission: A system in a vehicle that transmits power from the engine to the wheels.
OBD-II: On-Board Diagnostics, a standardized system for self-diagnostics in vehicles.
• Check for any additional trouble codes.
• Inspect the wiring and connectors to the pump motor.
• Test the motor for proper operation and resistance.
• Replace the faulty pump motor if necessary.
• Repair or replace damaged wiring or connectors.
• Update or reprogram the control module if needed.
• OBD-II scanner
• Multimeter
• Basic hand tools
$200 - $600
Moderate
• Toyota Prius
• Ford Fusion Hybrid
• Chevrolet Volt
• Regular maintenance of the transmission system
• Promptly address any warning lights
• Regular inspection of wiring and connectors
Transmission System Issue
• Do not ignore the warning light; have it checked as soon as possible.
• Avoid driving the vehicle if you notice transmission issues.
• Consult a professional mechanic for a thorough diagnosis.
Transmission components may be covered under the powertrain warranty. Check with your vehicle manufacturer.
The P277C code has been more common in hybrid vehicles due to their reliance on electric components for transmission operations.
High – This issue can lead to serious transmission problems if not addressed promptly.
Driving with a malfunctioning transmission can be dangerous and may lead to further damage.
• Vehicle at operating temperature
• Transmission in drive or reverse
The auxiliary transmission fluid pump B is typically located near the transmission assembly.
Q: Can I drive with a P277C code?
A: It's not recommended to drive with this code active as it can lead to transmission damage.
Q: How can I reset the P277C code?
A: The code can be reset with an OBD-II scanner, but it's important to fix the underlying issue first.
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