U0421moderate severityNetwork
Invalid Data Received From Suspension Control Module B
on 2014 Ram 2500 6.7L I6 Cummins Diesel · 4WD
What this code means
The network is receiving corrupted data from suspension control module B. This can cause poor ride quality or loss of suspension adjustment.
Symptoms
- Suspension warning light
- Harsh or uneven ride
- Ride height issues
Common causes
- Faulty suspension control module B
- Bus wiring or connector fault
- Corroded or loose connectors
- Software or programming error
Diagnostic steps
- Scan all modules for codes
- Check power and ground to suspension module B
- Inspect data bus wiring and connectors
- Review suspension module B live data with scan tool
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ANCEL AD410 →
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Serious DIY~$100
BlueDriver Pro →
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Autel MaxiCOM MK808S →
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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