U0425low severityNetwork
Invalid Data Received From Auxiliary Heater Control Module
on 2014 Ram 2500 6.7L I6 Cummins Diesel · 4WD
What this code means
The computer is getting bad data from the auxiliary heater control module. This can cause the auxiliary heater to malfunction or not run.
Symptoms
- Auxiliary heater not working
- Slow cabin warm-up
- Heater warning message
Common causes
- Faulty auxiliary heater control module
- 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 auxiliary heater module
- Inspect data bus wiring and connectors
- Review heater module live data with scan tool
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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