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 a part of the car that helps it move through the air better isn't getting enough power. It's like when a toy car's battery is low, and it can't go as fast.
The Active Aerodynamic Feature Control Module D is not receiving the expected voltage, which can affect the vehicle's aerodynamic systems.
The B3A31 code indicates a low voltage condition in the power mode circuit of the Active Aerodynamic Feature Control Module D. This module controls parts of the vehicle that adjust to improve aerodynamics, such as active grille shutters or spoilers. A low voltage condition suggests an issue with the power supply or wiring to the module.
• Reduced fuel efficiency
• Warning light on the dashboard
• Aerodynamic features not functioning properly
• Faulty wiring or connections
• Failed Active Aerodynamic Feature Control Module
• Battery or alternator issues
Aerodynamics: The way air moves around things.
Voltage: The force of an electric current.
• Check for any blown fuses related to the module.
• Inspect wiring and connectors for damage or corrosion.
• Test the battery and alternator for proper voltage output.
• Repair or replace damaged wiring or connectors.
• Replace the Active Aerodynamic Feature Control Module if faulty.
• Ensure battery and alternator are functioning correctly.
• Multimeter
• OBD-II scanner
• Basic hand tools
$100 - $500
Moderate
• Vehicle 1
• Vehicle 2
• Vehicle 3
• Regular maintenance checks on electrical systems.
• Ensure battery terminals are clean and secure.
• Avoid exposure to extreme weather conditions that can damage wiring.
Electrical Issue
• Have the vehicle inspected by a professional if the warning light appears.
• Avoid ignoring the issue as it may lead to reduced performance.
Check with the vehicle manufacturer for warranty coverage on electrical components.
This code often appears in vehicles with advanced aerodynamic features that rely on electronic control modules.
Moderate – The vehicle can still be driven, but performance and efficiency may be affected.
Driving with this issue may not be immediately dangerous, but it can lead to increased fuel consumption and emissions.
• Vehicle is on and running.
• Aerodynamic features are activated.
The Active Aerodynamic Feature Control Module is typically located near the front of the vehicle, often behind the grille or bumper.
Q: Can I drive my car with this code?
A: Yes, but it's best to get it checked soon to avoid reduced performance.
Q: Will this code affect my car's fuel efficiency?
A: Yes, it can lead to reduced fuel efficiency due to improper aerodynamic function.
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