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U0008: High Speed CAN Communication Bus (-) High

What Does U0008 Mean?

U0008 is a diagnostic trouble code indicating: High Speed CAN Communication Bus (-) High. This code relates to the network communication system. The vehicle's computer detected a condition outside normal operating parameters and stored this code.

What To Do Next

  1. 1
    Find your vehicle above

    Click your make and model for real owner reports and common causes specific to your vehicle.

  2. 2
    Check for recalls

    Go to nhtsa.gov/recalls and enter your VIN. Free repairs if covered.

  3. 3
    Get a professional diagnosis

    A code alone doesn't identify the exact failed part. A diagnostic ($50–$150) pinpoints the root cause.

Related Codes

U0003 High Speed CAN Communication Bus (+) Open U0004 High Speed CAN Communication Bus (+) Low U0005 High Speed CAN Communication Bus (+) High U0006 High Speed CAN Communication Bus (-) Open U0007 High Speed CAN Communication Bus (-) Low U0009 High Speed CAN Communication Bus (-) shorted to Bus (+) U0010 Medium Speed CAN Communication Bus U0011 Medium Speed CAN Communication Bus Performance