U0186low severityNetwork
Lost Communication With Audio Amplifier
on 2009 Audi A3 2.0L TDI · FWD
What this code means
A control module lost communication with the audio amplifier over the data bus. This can result in no sound or degraded audio output.
Symptoms
- No sound from speakers
- Distorted or intermittent audio
- Fault code stored
Common causes
- Faulty audio amplifier
- Wiring or connector fault
- Blown fuse or power loss to amplifier
- Damaged data bus circuit
Diagnostic steps
- Scan for related U-codes on all modules
- Check power and ground at amplifier
- Inspect bus wiring and connectors for damage
- Test module communication with scan tool
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00003
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01304
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01312
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01314
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01315
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01316
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01317
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01318
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01321
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U0001
High Speed CAN Communication Bus