Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means there's a problem with the buttons on the steering wheel that control things like the radio or phone. It's like when a TV remote button doesn't work right.
The P155A code indicates an issue with the communication between the multifunction steering wheel controls and the vehicle's main computer.
The P155A code is triggered when the vehicle's control module detects a fault in the toggle bit signal from the multifunction steering wheel interface. This could be due to a malfunction in the steering wheel buttons or a communication error between the steering wheel and the vehicle's control systems.
• Steering wheel buttons not responding
• Intermittent operation of steering wheel controls
• Warning light on the dashboard
• Faulty steering wheel control buttons
• Damaged wiring or connectors
• Faulty steering wheel control module
Multifunction Steering Wheel (MFL): A steering wheel with integrated controls for audio, phone, and other functions.
Toggle Bit: A binary signal used in digital communication to indicate a change in state.
• Check for any visible damage to the steering wheel buttons.
• Inspect wiring and connectors for damage or disconnection.
• Use a diagnostic tool to check for additional fault codes.
• Replace faulty steering wheel buttons.
• Repair or replace damaged wiring or connectors.
• Replace the steering wheel control module if necessary.
• OBD-II scanner
• Multimeter
• Screwdriver set
$100 - $500
Moderate
• BMW 3 Series
• Mercedes-Benz C-Class
• Audi A4
• Regularly check the functionality of steering wheel buttons.
• Ensure no liquids are spilled on the steering wheel.
• Have the vehicle's electrical system inspected during regular maintenance.
Sensor Issue
• Avoid using malfunctioning buttons until repaired.
• Schedule a service appointment if the issue persists.
Check with your vehicle manufacturer for warranty coverage on electrical components.
This code is commonly seen in vehicles with advanced steering wheel controls and can be due to wear and tear or accidental damage.
Moderate – It may not affect driving immediately, but should be addressed to ensure all vehicle controls function properly.
Ignoring this issue may lead to a loss of functionality in steering wheel controls, which could be distracting or inconvenient while driving.
• Vehicle in park or neutral
• Ignition in the ON position
The multifunction steering wheel controls are located on the steering wheel, typically on both sides of the wheel.
Q: Can I still drive my car with this code?
A: Yes, but some steering wheel controls may not work properly.
Q: Will this code affect my vehicle's performance?
A: No, it mainly affects the functionality of the steering wheel controls.
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