U2023low severityNetwork
Fault Received from External Node
on 2015 Kia Forte 1.8L I4 · FWD
What this code means
A control module has received a fault notification from another module on the network, indicating a dependent system has a problem.
Symptoms
- Warning light for secondary system
- Cascading DTCs across modules
- Feature limited due to external fault
- System in reduced functionality mode
Common causes
- Primary fault exists in another module
- Dependent system has active DTC
- Communication issue causing fault propagation
- Software glitch sending false fault signal
Diagnostic steps
- Scan all modules for DTCs
- Find the primary fault code
- Address the original fault first
- Clear codes after primary repair
- Retest all systems
Repair notes
This is a cascading code. Find and fix the original DTC in the source module first.
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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