U0403moderate severityNetwork
Invalid Data Received From Emissions Control Unit A
on 2007 Ram 3500 5.9L I6 Cummins · 4WD
What this code means
A module received invalid data from emissions control unit A. This can affect emissions system operation and monitoring.
Symptoms
- Check engine light on
- Emissions system fault
- Poor engine performance
Common causes
- Faulty emissions control unit A
- Wiring or connector fault
- CAN bus corruption
- Software or calibration mismatch
Diagnostic steps
- Scan for related fault codes
- Check emissions control unit data
- Inspect wiring and connectors
- Test network communication lines
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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