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 in the car that helps move the transmission fluid is getting too hot. It's like when you run too fast and start to feel really hot, and you need to cool down.
The code indicates that the electric or auxiliary pump responsible for moving transmission fluid has detected an over-temperature condition.
The P277D code is triggered when the Powertrain Control Module (PCM) detects that the electric or auxiliary transmission fluid pump B motor is operating at a temperature above the manufacturer's specified limit. This could be due to excessive load, a malfunctioning cooling system, or a fault in the pump itself.
• Transmission overheating warning light
• Reduced transmission performance
• Unusual noises from the transmission area
• Faulty electric/auxiliary transmission fluid pump
• Cooling system failure
• Electrical issues such as a short circuit or open circuit
PCM: Powertrain Control Module
OBD-II: On-Board Diagnostics, Second Generation
• Check for any transmission fluid leaks.
• Inspect the electric/auxiliary pump for signs of wear or damage.
• Test the electrical connections and wiring to the pump.
• Replace the faulty transmission fluid pump.
• Repair or replace damaged wiring or connectors.
• Ensure the cooling system is functioning properly.
• OBD-II scanner
• Multimeter
• Wrench set
$200 - $600
Moderate
• Toyota Prius
• Ford Fusion Hybrid
• Chevrolet Volt
• Regularly check and maintain transmission fluid levels.
• Ensure proper cooling system operation.
• Perform regular vehicle maintenance checks.
Transmission System Issue
• Avoid driving aggressively to prevent overheating.
• Have the vehicle inspected by a professional if the warning light appears.
• Monitor transmission performance regularly.
Transmission components might be covered under the powertrain warranty. Check with your vehicle manufacturer.
This code has been associated with hybrid and electric vehicles that utilize electric pumps for transmission fluid circulation.
Moderate – Addressing this issue promptly can prevent further damage to the transmission.
Ignoring transmission issues can lead to severe vehicle damage and safety hazards. Always consult a professional mechanic for repairs.
• Vehicle at operating temperature
• Transmission in drive mode
The electric/auxiliary transmission fluid pump is typically located near the transmission assembly, often on the side or bottom of the transmission housing.
Q: Can I drive with a P277D code?
A: It's not recommended to drive with this code active, as it can lead to transmission damage.
Q: How do I know if my transmission fluid pump is failing?
A: Signs include overheating, unusual noises, and reduced transmission performance.
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