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 sensor that checks how much electricity is going to the pump that helps move the transmission fluid. It's like when a toy's battery is giving too much power and the toy might get too hot.
The P1A71 code is triggered when the powertrain control module (PCM) detects a high voltage condition in the circuit that monitors the current of the electric or auxiliary transmission fluid pump.
The electric or auxiliary transmission fluid pump is responsible for maintaining the proper fluid pressure in the transmission, especially in hybrid or electric vehicles. The current sensor monitors the electrical current going to the pump. If the sensor detects a current that is higher than expected, it sends a signal to the PCM, which then triggers the P1A71 code.
• Check Engine Light is on
• Transmission may not shift properly
• Unusual noises from the transmission area
• Faulty electric/auxiliary transmission fluid pump
• Damaged or corroded wiring or connectors
• Faulty current sensor
PCM: Powertrain Control Module, the computer that controls engine and transmission functions.
OBD-II: On-Board Diagnostics, a standardized system in vehicles for self-diagnosis and reporting.
• Use an OBD-II scanner to confirm the P1A71 code.
• Inspect the wiring and connectors for damage or corrosion.
• Test the electric/auxiliary transmission fluid pump and current sensor for proper operation.
• Repair or replace damaged wiring or connectors.
• Replace the faulty current sensor.
• Replace the electric/auxiliary transmission fluid pump if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$200 - $600
Moderate
• Chevrolet Volt
• Toyota Prius
• Ford Fusion Hybrid
• Regularly inspect and maintain transmission components.
• Ensure electrical connections are clean and secure.
• Follow the manufacturer's maintenance schedule.
Sensor Issue
• Avoid driving the vehicle until the issue is resolved to prevent further damage.
• Consult a professional mechanic for a thorough inspection.
Check with the vehicle manufacturer for warranty coverage on transmission components.
The P1A71 code is more common in hybrid and electric vehicles due to their reliance on electric pumps for transmission fluid circulation.
Moderate – Addressing this issue promptly can prevent transmission damage.
Ignoring transmission issues can lead to unsafe driving conditions and further vehicle damage.
• Vehicle in park or neutral
• Engine running
The electric/auxiliary transmission fluid pump is typically located near the transmission assembly.
Q: Can I drive with a P1A71 code?
A: It's not recommended to drive with this code active, as it may lead to transmission damage.
Q: How is the P1A71 code diagnosed?
A: A mechanic will use an OBD-II scanner to confirm the code and inspect the wiring, connectors, and components related to the electric/auxiliary transmission fluid pump.
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