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 computer in your car detected a problem with the second fan that helps cool down the battery pack in a hybrid or electric vehicle. It's like a fan in your room not working properly to keep things cool.
The P0A99 code is triggered when the vehicle's control module detects a low voltage or poor performance in the circuit that controls the second cooling fan for the hybrid or electric vehicle's battery pack.
The P0A99 code indicates an issue with the control circuit for the second cooling fan that is responsible for maintaining the optimal temperature of the hybrid or EV battery pack. This could result from a low voltage condition, an open or short circuit, or a malfunctioning fan motor.
• Illuminated check engine light
• Reduced battery performance
• Overheating of the battery pack
• Faulty cooling fan motor
• Damaged wiring or connectors in the fan circuit
• Faulty control module
OBD-II: On-Board Diagnostics, a standardized system for vehicle self-diagnosis.
Control Module: A computer in the vehicle that manages specific functions.
• Inspect the cooling fan motor and its connections.
• Check for any blown fuses related to the fan circuit.
• Test the voltage and continuity in the fan control circuit.
• Replace the faulty cooling fan motor.
• Repair or replace damaged wiring or connectors.
• Replace the control module if necessary.
• Multimeter
• OBD-II scanner
• Screwdriver set
$200 - $600
Moderate
• Toyota Prius
• Chevrolet Volt
• Nissan Leaf
• Regularly inspect cooling fan operation.
• Ensure proper maintenance of electrical connections.
• Avoid overloading the vehicle's electrical system.
Electrical Circuit Issue
• Do not ignore the check engine light.
• Seek professional diagnosis if unsure.
• Monitor vehicle performance for any changes.
Repairs may be covered under the vehicle's powertrain or emissions warranty. Check with the manufacturer.
This code has been reported in hybrid and electric vehicles as they rely heavily on battery cooling systems.
Moderate – Addressing this issue promptly can prevent battery damage.
Operating a vehicle with a malfunctioning battery cooling system can lead to overheating and potential safety hazards.
• Vehicle should be at operating temperature.
• Ensure the battery pack is under load.
The cooling fan is typically located near the battery pack, often in the rear of the vehicle.
Q: What happens if I ignore this code?
A: Ignoring this code can lead to battery overheating and reduced vehicle performance.
Q: Can I drive with this code?
A: It's best to address the issue as soon as possible to avoid potential battery damage.
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