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 that the electric pump that helps move the transmission fluid isn't using as much power as it should. It's like when a toy car's motor isn't getting enough battery power to run properly.
The P0C27 code is triggered when the transmission control module (TCM) detects that the current draw from the auxiliary transmission fluid pump motor is below the expected range.
The electric or auxiliary transmission fluid pump is responsible for maintaining fluid pressure in the transmission. This pump is especially important in hybrid and electric vehicles where the engine may not always be running. The P0C27 code indicates that the pump motor is drawing less current than expected, which can be due to electrical issues or a malfunctioning pump.
• Check Engine Light illumination
• Transmission performance issues
• Unusual noises from the transmission area
• Faulty electric transmission fluid pump
• Electrical wiring issues or poor connections
• Failed transmission control module (TCM)
Transmission Control Module (TCM): A computer that manages the operation of the transmission.
Current Draw: The amount of electrical current used by a component.
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors to the pump for damage or corrosion.
• Test the electric transmission fluid pump for proper operation.
• Repair or replace damaged wiring or connectors.
• Replace the electric transmission fluid pump if faulty.
• Reprogram or replace the transmission control module if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$200 - $600
Moderate
• Toyota Prius
• Chevrolet Volt
• Ford Fusion Hybrid
• Regular maintenance of the transmission system
• Checking and securing electrical connections
• Using the correct transmission fluid
Sensor Issue
• Do not ignore the Check Engine Light.
• Have the vehicle inspected by a professional if unsure.
• Avoid driving the vehicle aggressively until repaired.
Check with your vehicle manufacturer for specific warranty coverage related to the transmission system.
This code is more common in hybrid and electric vehicles due to their reliance on electric pumps for transmission fluid circulation.
Moderate – While the vehicle may still operate, ignoring this issue can lead to transmission damage over time.
Driving with a malfunctioning transmission pump can lead to unsafe driving conditions and potential transmission failure.
• Vehicle at operating temperature
• Transmission in neutral or park
The electric transmission fluid pump is typically located near the transmission assembly and may be integrated into the transmission housing.
Q: Can I drive with a P0C27 code?
A: It's not recommended to drive for extended periods with this code, as it can lead to transmission damage.
Q: How is the transmission fluid pump tested?
A: A technician will use a multimeter to check for proper voltage and current at the pump.
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