U2031moderate severityNetwork
Lost Communication With Component
on 2003 Saturn L-Series 2.2L I4 · FWD
What this code means
The module reports a loss of serial data communication with a networked component. This indicates a break or fault in the vehicle communication network affecting data exchange.
Symptoms
- Warning lights illuminated
- Loss of some vehicle functions
- Intermittent module operation
Common causes
- Faulty control module
- Open or shorted CAN bus wiring
- Corroded or loose connectors
- Low system voltage
Diagnostic steps
- Scan all modules for stored codes
- Inspect network wiring and connectors
- Check power and ground to affected module
- Test CAN bus resistance and continuity
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Serious DIY~$100
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Autel MaxiSys MS906 Pro →
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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