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 thinks the pump that helps move transmission fluid isn't working well enough. It's like when a water pump in a fountain isn't pushing enough water.
The code P27E1 is triggered when the transmission control module (TCM) detects that the pressure from the auxiliary transmission fluid pump is below the expected level.
The electric or auxiliary transmission fluid pump is responsible for maintaining the necessary hydraulic pressure in the transmission system, especially in vehicles with start-stop systems. If the pressure is too low, it may indicate a problem with the pump, a leak, or an issue with the pressure sensor.
• Transmission slipping
• Delayed or harsh gear shifts
• Illuminated check engine light
• Reduced fuel efficiency
• Unusual noises from the transmission
• Faulty electric/auxiliary transmission fluid pump
• Low transmission fluid level
• Transmission fluid leak
• Faulty pressure sensor
• Electrical issues such as damaged wiring or connectors
Transmission: A system in a vehicle that transmits power from the engine to the wheels.
Hydraulic Pressure: The pressure exerted by a fluid within a closed system, used to perform work.
• Check the transmission fluid level and condition.
• Inspect for transmission fluid leaks.
• Test the electric/auxiliary transmission fluid pump operation.
• Check the wiring and connectors for damage or corrosion.
• Use a scan tool to monitor the pressure sensor readings.
• Refill or change the transmission fluid if necessary.
• Repair any leaks in the transmission system.
• Replace the faulty electric/auxiliary transmission fluid pump.
• Repair or replace damaged wiring or connectors.
• Replace the faulty pressure sensor.
• OBD-II scanner
• Multimeter
• Transmission fluid pressure gauge
• Basic hand tools
• Transmission fluid
$200 - $800
Moderate
• Ford F-150
• Chevrolet Silverado
• Toyota Camry
• Regularly check and maintain transmission fluid levels.
• Inspect transmission system for leaks periodically.
• Ensure electrical connections are clean and secure.
Transmission Performance
• Avoid driving the vehicle until the issue is resolved to prevent further damage.
• Consult with a professional mechanic for an accurate diagnosis and repair.
Check with the vehicle manufacturer for warranty coverage on transmission components.
This code has become more common with the advent of electric and hybrid vehicles, which rely on auxiliary pumps for transmission fluid pressure.
High – Driving with this issue can lead to significant transmission damage.
Ignoring this code can lead to transmission failure, which may result in loss of vehicle control.
• Vehicle at operating temperature
• Transmission in various gear states
The electric/auxiliary transmission fluid pump is typically located near the transmission or integrated within the transmission housing.
Q: Can I drive my car with code P27E1?
A: It's not recommended to drive with this code active, as it can cause further transmission damage.
Q: How do I reset the check engine light after fixing the issue?
A: You can use an OBD-II scanner to clear the code, or disconnect the battery for a few minutes, but ensure the issue is resolved first.
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