Revision of AdBlue Additive Pump Iveco

The 504381868 is the AdBlue/urea supply module of the SCR system for Iveco commercial vehicles. The assembly integrates the transfer pump from the tank to the dosing circuit, with control and safety components that allow stable supply of the reductant to the exhaust-line injector.

Technical features

• Operating voltage: 24 V (commercial vehicle electrical system).
• Function: withdrawal and pressurization of DEF (AdBlue) from the tank, line pressure maintenance, recirculation and feeding of the SCR injector.
• Typical integrated components: electric pump, pressure sensor/control, internal valves and quick connections for supply/return lines.
• Interfacing: command/diagnosis through the vehicle's SCR unit; monitoring of pressure and fluid temperature for the management of strategies.
• Usage specifications: AdBlue fluid (32.5% urea), circuit designed to resist crystallization and freezing with protection/heating devices managed at system level.

DIPA can intervene to overhaul these modules thanks to its experience and expertise.

Functionality

• Reductant supply: draws and delivers AdBlue to the injector with target pressure according to SCR maps.
• Pressure stabilization: controls the pressure ramp and compensates losses/variations in temperature and viscosity.
• Recirculation/priming: manages priming and emptying/recirculation phases to prevent deposits and crystallization.
• Diagnostics: allows monitoring of pressure and flow; in case of anomaly it triggers derating or safety locks commanded by the engine/SCR control unit.

Model applications

• Iveco Stralis
• Iveco Trakker
• Iveco Eurocargo Euro 6
• Iveco X-Way

Typical faults

• Insufficient reductant pressure due to pump wear, partially clogged filter or internal crystallization → difficulties in priming, increased noise, abnormal returns to the tank.
• Pressure loss during operation due to micro-leaks, internal valves not sealing or SCR injector stuck/open.
• Faulty integrated/line pressure sensor with unstable readings → repeated priming cycles and failure to stabilize.
• Electrical failures: power supply, ground, connector oxidation interrupting the command phase.
• Freezing/insufficient circuit heating with cold-start alarms and delayed SCR activation.

Final conclusions

The OE AdBlue pump 504381868 is a key component of the Iveco SCR chain: it ensures supply and pressure stability to the injector. The most frequent issues stem from crystallization, blockages or internal sensor/seal faults that lead to malfunctions.

DIPA offers a wide range of spare parts: from original items to aftermarket parts selected among the best manufacturers on the market. In addition, it supplies reconditioned components with performance equivalent to new, providing savings on replacement and contributing to environmental protection through the circular economy. If the spare part you need is not available, don't worry: DIPA can recondition your part on demand, returning full functionality and safety in a short time.