Audio Amplifier Communication Lost
The control module (typically the infotainment head unit or audio amplifier module) has detected a loss of communication on the serial data bus (CAN, MOST, A2B, or other proprietary protocol) with the audio amplifier. This code indicates that periodic status or data messages have not been received within a calibrated time, disabling amplified audio function.
1. Commonly Affected Makes
This is a generic OBD2 code, potentially applicable to any manufacturer using this diagnostic standard.
2. Most Common Causes
- Open, short to ground/battery, or corroded wiring/connectors in the amplifier communication bus
- Internal failure of the audio amplifier module
- Internal failure of the infotainment control module (transmitter/receiver)
- Low battery voltage or voltage spikes causing module resets
- Software error or need for reprogramming/calibration update in related modules
- Physical damage to the data bus (e.g., broken fiber optic cable in MOST systems)
3. Symptoms You Will Notice
- No sound from amplified speakers (e.g., door speakers, subwoofer)
- Audio system may display an error message or function with reduced features
4. Step-by-Step Diagnosis
Check battery voltage and charging system for proper operation
Inspect wiring and connectors at the audio amplifier and infotainment module for damage, corrosion, or loose connections
Use a scan tool to verify communication on the data bus and check for related codes
Perform a network test to isolate the non-communicating module
If applicable, inspect fiber optic cables for breaks or kinks (MOST systems)
Check for technical service bulletins (TSBs) regarding software updates or known issues
5. Frequently Asked Questions
Is it safe to drive?▼
Yes, the vehicle remains drivable. Only the amplified audio function is affected; safety systems are not impacted.
How much does it cost to fix?▼
Repair costs vary widely: from $100-$300 for a wiring repair to $500-$1500+ for module replacement or reprogramming.