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 special pump in your car that helps move transmission fluid isn't working right. It's like a helper that got stuck and isn't doing its job.
The P27A3 code indicates an issue with the performance or operation of the auxiliary transmission fluid pump B, which may be stuck in the 'off' position.
The auxiliary transmission fluid pump B is responsible for maintaining the necessary hydraulic pressure in the transmission system, especially in conditions where the main pump may not be sufficient. The P27A3 code is triggered when the vehicle's control module detects that this pump is not performing as expected or is stuck in the 'off' position.
• Transmission overheating
• Poor transmission performance
• Illuminated check engine light
• Faulty auxiliary transmission fluid pump B
• Electrical issues such as wiring problems or blown fuses
• Control module malfunction
Transmission: A system in a vehicle that transmits power from the engine to the wheels.
Hydraulic Pressure: Pressure created by fluid in a closed system, used to power various vehicle components.
• Check for other related codes that may provide additional context.
• Inspect the wiring and connections to the auxiliary transmission fluid pump B.
• Test the operation of the pump using diagnostic tools.
• Replace the faulty auxiliary transmission fluid pump B.
• Repair or replace damaged wiring or connectors.
• Reprogram or replace the control module if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$200 - $800
Moderate
• Vehicle 1
• Vehicle 2
• Vehicle 3
• Regular maintenance of the transmission system
• Timely replacement of transmission fluid
• Regular inspection of electrical connections
Transmission Performance Issue
• Do not ignore the check engine light.
• Consult a professional mechanic for a thorough diagnosis.
• Avoid driving the vehicle for long distances until the issue is resolved.
Check with the vehicle manufacturer for specific warranty coverage related to transmission components.
This code has been associated with vehicles that have advanced transmission systems that rely on electric pumps for optimal performance.
Moderate – Addressing this issue promptly can prevent further transmission damage.
Driving with a malfunctioning transmission can lead to unsafe driving conditions. Ensure repairs are conducted by a qualified professional.
• Vehicle at operating temperature
• Transmission in various gear positions
The auxiliary transmission fluid pump B is typically located near the transmission assembly, often mounted externally.
Q: Can I drive my car with a P27A3 code?
A: It's not recommended to drive for long distances as it may cause further transmission damage.
Q: How can I reset the check engine light for this code?
A: The light can be reset with an OBD-II scanner, but it's important to fix the underlying issue first.
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