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 transmission fluid. It's like if a helper was supposed to push water through a pipe, but they were pushing too hard.
The P27A5 code indicates that the control circuit for the auxiliary transmission fluid pump B is experiencing a high voltage condition.
The P27A5 code is triggered when the powertrain control module (PCM) detects a high voltage condition in the control circuit of the auxiliary transmission fluid pump B. This pump is responsible for maintaining proper fluid pressure in the transmission, especially in stop-and-go traffic or when the engine is not running.
• Check Engine Light illuminated
• Transmission may not shift properly
• Unusual noises from the transmission
• Faulty auxiliary transmission fluid pump B
• Short circuit in the pump control circuit
• Faulty PCM or transmission control module (TCM)
PCM: Powertrain Control Module
TCM: Transmission Control Module
• Use an OBD-II scanner to confirm the code and check for other related codes.
• Inspect the wiring and connectors for the auxiliary transmission fluid pump B for damage or corrosion.
• Test the auxiliary transmission fluid pump B for proper operation and voltage levels.
• Repair or replace damaged wiring or connectors.
• Replace the faulty auxiliary transmission fluid pump B.
• Reprogram or replace the PCM/TCM if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$200 - $600
Moderate
• Ford F-150
• Chevrolet Silverado
• Toyota Camry
• Regularly check and maintain transmission fluid levels.
• Inspect wiring and connectors for corrosion or damage.
• Follow the vehicle's maintenance schedule.
Sensor Issue
• Have the vehicle inspected by a professional mechanic.
• Avoid driving the vehicle until the issue is resolved to prevent further damage.
Repairs may be covered under the vehicle's powertrain warranty. Check with the manufacturer or dealership.
This code has been reported in vehicles with electric transmission fluid pumps, especially in models with start-stop systems.
Moderate – Address the issue promptly to avoid transmission damage.
Ignoring this code may lead to transmission failure, which can be dangerous while driving.
• Vehicle at operating temperature
• Transmission in gear
The auxiliary transmission fluid pump is typically located near the transmission housing.
Q: Can I drive with a P27A5 code?
A: It's not recommended to drive with this code as it may lead to transmission damage.
Q: How do I clear a P27A5 code?
A: After repairs, use an OBD-II scanner to clear the code. If the issue is resolved, the code should not return.
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