U0077
Control Module Communication Bus E Off
U0077 is an OBD-II diagnostic trouble code meaning: Control Module Communication Bus E Off. Common causes: can bus wire break, short circuit in can circuit. Estimated repair cost: $6–56.
Symptoms
- Unstable engine operation
- Check Engine Light Is On
- No communication with diagnostic scanner
- Incorrect operation of other vehicle systems
Causes
- CAN bus wire break
- Short circuit in CAN circuit
- Faulty electronic control unit E
- Damage to connectors or corrosion of contacts
How to Fix
- Check the integrity of the CAN bus wires
- Check connectors and contacts for damage
- Diagnose electronic control unit E
- Replace damaged wires or connectors
Related codes
Error U0077 by Vehicle Brand
FAQ
What does the U0077 code mean?
U0077 is an OBD-II diagnostic trouble code that indicates: Control Module Communication Bus E Off
What causes a U0077 error code?
The most common causes of U0077 include: CAN bus wire break; Short circuit in CAN circuit; Faulty electronic control unit E; Damage to connectors or corrosion of contacts.
How do I fix a U0077 diagnostic trouble code?
To fix U0077: Check the integrity of the CAN bus wires. Check connectors and contacts for damage. Diagnose electronic control unit E. For a complete diagnosis, use an OBD-II scanner.
Is it safe to drive with U0077?
Limited driving only, diagnose soon
How much does it cost to fix U0077?
The estimated repair cost for U0077 is $6–56. Actual cost depends on your vehicle, location, and labor rates.
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