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 is having trouble communicating with the system that helps control how much power the engine uses. It's like when you try to talk to a friend on the phone, but the call keeps dropping.
The P320B code is triggered when the Engine Control Module (ECM) detects a timeout in receiving messages related to torque calculation from the Active Front Steering (AFS) system.
The P320B code indicates that the ECM is not receiving timely or expected data from the AFS system regarding torque calculations. This could be due to a communication error or a fault within the AFS system itself. The ECM relies on this data to adjust engine performance and steering dynamics.
• Check Engine Light illuminated
• Steering performance issues
• Reduced engine power
• Faulty AFS module
• Wiring issues or poor connections
• ECM software glitch
ECM: Engine Control Module
AFS: Active Front Steering
• Use an OBD-II scanner to confirm the code.
• Inspect wiring and connectors related to the AFS system.
• Check for any software updates for the ECM.
• Repair or replace faulty wiring or connectors.
• Update ECM software if available.
• Replace the AFS module if necessary.
• OBD-II scanner
• Multimeter
• Diagnostic software
$200 - $800
Moderate
• BMW 3 Series
• Audi A4
• Mercedes-Benz C-Class
• Regular maintenance checks
• Ensure all software updates are applied
• Inspect wiring harnesses periodically
Communication Error
• Do not ignore the Check Engine Light.
• Consult a professional mechanic for diagnosis.
• Avoid driving aggressively until the issue is resolved.
Check with your vehicle manufacturer for warranty coverage on the AFS system and ECM.
This code has been reported in vehicles with advanced steering systems that rely on electronic communication between modules.
Moderate – Addressing this issue promptly can prevent further complications.
Driving with a malfunctioning steering system can be dangerous. Ensure the vehicle is safe to operate.
• Vehicle in motion
• Steering inputs being made
The AFS module is typically located near the steering column or integrated within the steering rack.
Q: Can I drive with a P320B code?
A: It's not recommended to drive extensively with this code as it can affect steering performance.
Q: Will resetting the code fix the problem?
A: Resetting the code may temporarily clear the Check Engine Light, but it won't fix the underlying issue.
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