OBD2 code U0099: CAN communication bus - Network fault
CAN bus communication fault.
Detected Root Component
Network Component
Observed Symptoms
- Loss of communication between modules
- Dashboard errors
- Unresponsive module
Possible Causes
- Damaged CAN wiring
- Missing CAN termination resistor
- CAN bus short circuit module
- Damaged wiring
Tools Required
Interactive Diagnostic
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Diagnostic Result
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Parts likely to be the cause (Moteur (général))
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Frequently asked questions about code U0099
What does code U0099 mean? ▾
OBD2 code U0099: CAN communication bus - Network fault. CAN bus communication fault.
What are the symptoms of code U0099? ▾
Code U0099 may cause: Loss of communication between modules, Dashboard errors, Unresponsive module. The intensity of these symptoms varies depending on the vehicle and driving conditions.
What causes code U0099? ▾
The most common causes of code U0099 are: Damaged CAN wiring, Missing CAN termination resistor, CAN bus short circuit module, Damaged wiring. A proper OBD2 diagnostic will pinpoint the exact cause.
Is it serious to drive with code U0099? ▾
Yes, code U0099 is critical (Critical). Avoid driving and consult a professional promptly to prevent major damage.
How do I fix code U0099? ▾
Start by reading the code with an OBD2 scanner, then follow the interactive decision tree on this page. Priority causes to check: Damaged CAN wiring, Missing CAN termination resistor, CAN bus short circuit module, Damaged wiring. Difficulty: Medium · Estimated time: 30-60min.