U2023low severityNetwork
Fault Received from External Node
on 2000 Audi A6 2.8L V6 · AWD
What this code means
A control module has received a fault notification from another module on the network, indicating a dependent system has a problem.
Symptoms
- Warning light for secondary system
- Cascading DTCs across modules
- Feature limited due to external fault
- System in reduced functionality mode
Common causes
- Primary fault exists in another module
- Dependent system has active DTC
- Communication issue causing fault propagation
- Software glitch sending false fault signal
Diagnostic steps
- Scan all modules for DTCs
- Find the primary fault code
- Address the original fault first
- Clear codes after primary repair
- Retest all systems
Repair notes
This is a cascading code. Find and fix the original DTC in the source module first.
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Other Network codes on this vehicle
00003
Control Module - Defective
01304
Radio - No Communication
01312
Powertrain Data Bus - Defective
01314
Engine Control Module (ECM) - no communications
01315
Transmission Control Module (TCM) - No Communication
01316
ABS Control Module - No Communication
01317
Instrument Cluster Control Module (J285) - No Communication
01318
Immobilizer Control Module - No Communication
01321
Airbag Control Module - No Communication
U0001
High Speed CAN Communication Bus