Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
The car has a special pump that helps with the transmission fluid, and it's not turning off when it should.
This code indicates that the electric or auxiliary pump for the transmission fluid, labeled as Pump B, is continuously running when it should not be.
The P27A6 code is triggered when the transmission control module (TCM) detects that the auxiliary transmission fluid pump B is stuck in the 'on' position. This pump is responsible for maintaining the proper flow and pressure of transmission fluid, especially in hybrid or electric vehicles where the engine may not always be running.
• Check Engine Light is on
• Unusual noise from the transmission area
• Decreased fuel efficiency
• Faulty transmission fluid pump B
• Electrical short in the pump circuit
• Defective transmission control module (TCM)
Transmission Fluid: A liquid used to lubricate and cool the components of a vehicle's transmission.
Transmission Control Module (TCM): An electronic device that controls the operation of a vehicle's transmission.
• Use an OBD-II scanner to confirm the code
• Inspect the wiring and connections to the pump
• Test the pump for proper operation
• Replace the faulty transmission fluid pump B
• Repair or replace damaged wiring
• Reprogram or replace the transmission control module
• OBD-II scanner
• Multimeter
• Basic hand tools
$200 - $600
Moderate
• Toyota Prius
• Ford Fusion Hybrid
• Chevrolet Volt
• Regular maintenance of the transmission system
• Check for recalls related to transmission components
• Ensure proper fluid levels are maintained
Transmission System Issue
• Avoid driving the vehicle until repaired
• Consult a professional mechanic for diagnosis
• Check for any related recalls
Transmission components may be covered under powertrain warranty.
This code has been more prevalent in hybrid vehicles due to the reliance on electric pumps.
Moderate – While the vehicle may still be drivable, ignoring this issue can lead to further transmission damage.
Driving with a faulty transmission pump can lead to safety hazards and increased wear on the transmission.
• Vehicle at operating temperature
• Transmission in normal operating mode
The electric/auxiliary transmission fluid pump is typically located near the transmission assembly.
Q: Can I drive with the P27A6 code?
A: It's not recommended to drive with this code as it can lead to further transmission issues.
Q: How is the transmission fluid pump tested?
A: A mechanic can test the pump using a multimeter and by checking for proper operation with an OBD-II scanner.
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