U0040high severityNetwork
Control Module Communication Bus D Low
on 2021 Dodge Durango 6.2L V8 Supercharged · 4WD
What this code means
The D communication bus voltage is too low, interrupting data exchange between modules. Systems on this bus may lose communication.
Symptoms
- Warning lights illuminated
- Module communication loss
- Intermittent faults
Common causes
- Bus D shorted to ground
- Corroded or loose connectors
- Failed control module
- Damaged wiring harness
Diagnostic steps
- Scan all modules for codes
- Inspect bus D wiring for shorts
- Measure bus D voltage with scope
- Isolate modules to locate fault
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ANCEL AD410 →
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Serious DIY~$100
BlueDriver Pro →
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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