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 electric pump that helps move the transmission fluid in your car is getting too hot.
The P1A55 code indicates that the control module for the electric or auxiliary transmission fluid pump has detected an over-temperature condition.
The electric or auxiliary transmission fluid pump is responsible for circulating the transmission fluid, which helps in cooling and lubricating the transmission components. The control module monitors the temperature of the pump to ensure it operates within a safe range. If the temperature exceeds the predefined limits, the P1A55 code is triggered.
• Transmission overheating warning light
• Reduced transmission performance
• Unusual noises from the transmission
• Faulty transmission fluid pump
• Blocked transmission fluid lines
• Malfunctioning temperature sensor
Transmission Fluid: A liquid used to lubricate and cool the components of a vehicle's transmission.
Control Module: An electronic device that manages various functions in a vehicle.
• Check for any transmission fluid leaks.
• Inspect the transmission fluid pump for proper operation.
• Verify the temperature sensor readings.
• Replace the faulty transmission fluid pump.
• Clear any blockages in the transmission fluid lines.
• Replace the malfunctioning temperature sensor.
• OBD-II scanner
• Multimeter
• Wrench set
$300 - $800
Moderate
• Chevrolet Volt
• Cadillac ELR
• Toyota Prius
• Regular transmission fluid checks
• Routine maintenance of the transmission system
• Ensure proper cooling system operation
Temperature Issue
• Avoid driving the vehicle until the issue is resolved.
• Consult with a professional mechanic for a thorough inspection.
Check with the vehicle manufacturer for warranty coverage on transmission components.
This code has been reported in hybrid and electric vehicles with auxiliary transmission fluid pumps.
High – Continued driving may cause severe transmission damage.
Ignoring this code may lead to transmission failure, which can be hazardous while driving.
• Vehicle at operating temperature
• Transmission system engaged
The electric transmission fluid pump is typically located near the transmission assembly.
Q: Can I drive with a P1A55 code?
A: It's not recommended to drive with this code active, as it could lead to further transmission damage.
Q: How do I reset the P1A55 code?
A: After repairs, use an OBD-II scanner to clear the code. If the issue persists, further diagnosis is needed.
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