U0042high severityNetwork
Control Module Communication Bus D High
on 1998 Dodge Dakota 3.9L V6 Magnum · 4WD
What this code means
The D communication bus voltage is reading too high, disrupting data flow. Modules on this bus may fail to communicate.
Symptoms
- Dashboard warning lights
- Loss of module functions
- Intermittent faults
Common causes
- Bus D shorted to power
- Wiring insulation damage
- Failed control module
- Corroded connectors
Diagnostic steps
- Scan for stored codes
- Inspect bus D wiring for shorts to power
- Measure bus D voltage with scope
- Isolate modules to find source
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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