U0258low severityNetwork
Lost Communication With Auxiliary Heater Control Module
on 2014 Ram 2500 6.7L I6 Cummins Diesel · 4WD
What this code means
The network lost communication with the auxiliary heater control module. The auxiliary or supplemental heater may not operate.
Symptoms
- Auxiliary heater not working
- Slow cabin warm-up
- Heater warning message
Common causes
- Faulty auxiliary heater control module
- Wiring or connector fault
- Power or ground loss
- Bus communication fault
Diagnostic steps
- Scan for stored codes
- Check module power and ground
- Inspect bus wiring and connectors
- Replace heater module if faulty
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ANCEL AD410 →
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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