U0493 Data Integrity Fault on CAN Bus
Diagnostic trouble code U0493 indicates a data integrity issue on the vehicle's CAN bus network. Specifically, a receiving control module has detected invalid or corrupted data from the Personal Computer Module (often a telematics or diagnostic device). Unlike a total loss of communication, this code means the data frames are corrupt, out of range, or fail checksum validation. This can be caused by electromagnetic interference, a failed software update, or a faulty peripheral module sending bad packets.
1. Commonly Affected Makes
This is a generic OBD2 code, potentially applicable to any manufacturer using this diagnostic standard.
2. Most Common Causes
- Electromagnetic interference (EMI) on the CAN bus
- Peripheral control module or diagnostic device sending corrupt data
- Failed software or firmware update in the vehicle's computer
- Damaged data bus wiring or poor ground connection
- Internally damaged personal computer module (telematics/diagnostic)
3. Symptoms You Will Notice
- Check Engine Light illuminated
- Possible intermittent communication issues with telematics or diagnostic tools
4. Step-by-Step Diagnosis
Scan for all stored codes and freeze frame data
Inspect CAN bus wiring for damage, corrosion, or poor connections
Check for aftermarket devices connected to the OBD-II port
Perform a network integrity test to isolate the faulty module
Verify and reflash software updates if applicable
5. Frequently Asked Questions
Is it safe to drive?▼
Yes, the severity is low. The vehicle may still be drivable, but it's recommended to diagnose and repair the issue to prevent potential communication problems with other modules.
How much does it cost to fix?▼
Costs vary widely: from $50–$150 for a simple wiring repair or reflash, up to $500–$1,000 if a module needs replacement.