U0049
NetworkModule Communicationhigh severityControl Module Communication Bus D Open
What U0049 Means
An open circuit has been detected on communication bus D. Data cannot pass between the affected modules.
Symptoms
- Modules not communicating
- Warning lights active
- Features inoperative
Common Causes
- Broken bus D wire
- Loose or disconnected connector
- Faulty control module
- Corroded terminals
Diagnostic Steps
- Scan all modules for codes
- Check bus D continuity
- Inspect connectors for damage
- Test module power and ground
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