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 part of the car that helps pump the transmission fluid is getting too hot. It's like when a toy motor gets too hot if it runs for too long.
The transmission fluid pump driver is responsible for circulating fluid in the transmission. If it overheats, it can lead to performance issues.
The P1AC4 code indicates that the electric or auxiliary transmission fluid pump driver has exceeded its normal operating temperature. This could be due to excessive load, electrical issues, or component failure.
• Transmission overheating
• Warning light on the dashboard
• Reduced vehicle performance
• Faulty electric transmission fluid pump
• Electrical wiring issues
• Excessive load on the transmission
Transmission: A system in a vehicle that transmits power from the engine to the wheels.
OBD-II: On-Board Diagnostics, a system that monitors vehicle performance.
• Check for any stored trouble codes.
• Inspect the wiring and connections to the pump.
• Test the operation of the transmission fluid pump.
• Replace the electric transmission fluid pump if faulty.
• Repair or replace damaged wiring.
• Ensure the transmission is not overloaded.
• OBD-II scanner
• Multimeter
• Wrench set
$200 - $600
Moderate
• Chevrolet Volt
• Cadillac ELR
• Chevrolet Malibu Hybrid
• Regular maintenance checks
• Avoid overloading the vehicle
• Ensure proper fluid levels
Transmission System Issue
• Do not ignore the warning light.
• Get the vehicle checked by a professional.
• Avoid driving long distances until fixed.
Check vehicle warranty for coverage on transmission components.
This code has been more common in hybrid vehicles with electric transmission pumps.
Moderate – Should be addressed soon to prevent further damage.
Driving with a malfunctioning transmission can lead to safety issues. Always address warning lights promptly.
• Vehicle at operating temperature
• Transmission fluid at correct level
The electric transmission fluid pump is typically located near the transmission assembly.
Q: Can I drive with a P1AC4 code?
A: It's not recommended to drive for long distances as it may cause further damage.
Q: How can I prevent this issue?
A: Regular maintenance and not overloading the vehicle can help prevent overheating.
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