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 the transmission fluid. It's not getting enough power.
The P1AAC code is triggered when the vehicle's control module detects that the voltage supply to the electric or auxiliary transmission fluid pump is lower than expected.
The electric or auxiliary transmission fluid pump is responsible for circulating transmission fluid within the transmission system, especially in hybrid or electric vehicles. This code indicates that the voltage supply to this pump is below the threshold needed for proper operation, which could affect the transmission's performance.
• Transmission overheating
• Poor transmission performance
• Illuminated check engine light
• Faulty electric transmission fluid pump
• Wiring issues such as short circuits or open circuits
• Faulty control module or relay
Transmission: A system in a vehicle that transmits power from the engine to the wheels.
Voltage: The electrical potential difference, which powers electronic components.
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors to the transmission fluid pump.
• Check the voltage supply to the pump.
• Repair or replace damaged wiring or connectors.
• Replace the electric transmission fluid pump if faulty.
• Replace or reprogram the control module if necessary.
• OBD-II scanner
• Multimeter
• Wrench set
$200 - $800
Moderate
• Chevrolet Volt
• Toyota Prius
• Ford Fusion Hybrid
• Regular maintenance checks
• Ensure proper battery voltage levels
• Inspect wiring harnesses periodically
Electrical Issue
• Avoid driving the vehicle until repaired to prevent further damage.
• Consult a professional mechanic for a thorough inspection.
Check with your vehicle's manufacturer for warranty coverage on the transmission system.
This code has become more common with the rise of hybrid and electric vehicles that use electric pumps for transmission fluid circulation.
Moderate – It should be addressed soon to avoid potential transmission damage.
Operating a vehicle with transmission issues can lead to unsafe driving conditions.
• Vehicle in operation
• Transmission fluid at operating temperature
The electric transmission fluid pump is typically located near the transmission assembly.
Q: Can I drive with a P1AAC code?
A: It's not recommended to drive with this code as it can lead to transmission damage.
Q: How do I reset the P1AAC code?
A: After repairs, use an OBD-II scanner to clear the code. If the issue is resolved, it should not return.
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