| Fault Code | Description | Likely Cause | |------------|-------------|----------------| | | RFC – Additive level too low | Additive tank empty or level sensor failure | | 4742 | RFC – Additive dosing circuit malfunction | Clogged injector, pump failure, or blocked line | | 4743 | RFC – Additive pressure sensor fault | Faulty pressure sensor in dosing unit | | 4744 | RFC – Communication error between ECU and RFC controller | CAN bus interruption, wiring issue, or faulty RFC module | | 4745 | RFC – Additive quality error | Wrong or degraded additive (non-genuine fluid) | | 4746 | RFC – Additive temperature out of range | Sensor failure or heater malfunction (cold climates) | | 4747 | RFC – DPF efficiency low due to missing additive | Additive system disabled or empty for long period | | SPN 5394 / FMI 0-16 (J1939) | RFC Additive Tank Level – Low / Data erratic | Level sensor or wiring short |
: If accompanied by brake or air warnings, it may indicate a defective air pressure sensor or broken wiring on top of the Air Processing Unit (Air Dryer) located in the middle of the chassis. Typical Causes and Solutions Incorrect Bulbs iveco stralis rfc fault codes