U0300moderate severityNetwork
Internal Control Module Software Incompatibility
on 2009 Kia Optima 2.4L I4 · FWD
What this code means
Software version mismatch between communicating modules causing data interpretation errors.
Symptoms
- Warning lights on
- Systems behaving erratically
- Features not working correctly after update
- Communication errors between modules
Common causes
- Module software not updated together
- Partial software update
- Incorrect software version flashed
- Aftermarket module with wrong software
Diagnostic steps
- Check software versions on all modules
- Compare to required version table
- Perform full vehicle software update
- Check for TSBs regarding software updates
Repair notes
Perform complete vehicle software update. All related modules must be updated together.
Other Network codes on this vehicle
U0001
High Speed CAN Communication Bus
U0002
High Speed CAN Communication Bus Performance
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
U0008
High Speed CAN Communication Bus (-) High
U0009
High Speed CAN Communication Bus Shorted Together
U0010
Medium Speed CAN Communication Bus