U0030high severityNetwork
Control Module Communication Bus C Low
on 2015 Tesla Model X 90 kWh Dual Motor AWD · AWD
What this code means
The C communication bus voltage is too low, disrupting data flow between modules. Affected systems may lose communication and trigger warnings.
Symptoms
- Warning lights illuminated
- Loss of module functions
- Intermittent communication faults
Common causes
- Bus C wiring shorted to ground
- Loose or corroded connectors
- Failed control module on bus C
- Damaged wiring harness
Diagnostic steps
- Scan all modules for codes
- Inspect bus C wiring for shorts
- Measure bus C voltage with scope
- Isolate modules to locate fault
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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