U0259low severityNetwork
Lost Communication With Fuel Fired Heater Control Module
on 2013 Ram 2500 6.7L I6 Cummins Diesel · 4WD
What this code means
The vehicle's network has lost contact with the fuel fired heater control module. This is usually a wiring or module fault affecting the auxiliary heater.
Symptoms
- No or weak cabin heat
- Warning light on dash
- Auxiliary heater inoperative
Common causes
- Faulty wiring or connector to heater module
- Failed fuel fired heater control module
- Blown fuse or power supply issue
- Corrupted CAN bus network
Diagnostic steps
- Scan for related communication codes
- Check power and ground at heater module
- Inspect wiring and connectors for damage
- Test CAN bus continuity to module
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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